# U.S. Government Printing Office Style Manual/Spelling

In addition to indicating the preferred forms of words with variant spellings, the list also contains other words frequently misspelled or causing uncertainty. (See also "Word Division," a supplement to the GPO Style Manual.)
    A
    abattoir
    aberration
    abetter
       abettor (law)
    abridgment
    absorb (take in)
    adsorb (adhesion)
    abysmal
    a cappella
    accede (yield)
       exceed (surpass)
    accepter
       acceptor (law)
    accessory
    accommodate
    accordion
    accouter
    accursed
    acetic (acid)
       ascetic (austere)
    acknowledgment
    acoustic
    adapter
    adjurer
    adjuster
    ad nauseam
    adviser
       advisor (law)
    adz
    aegis
    aesthetic
    affect (influence, v.)
       effect (result, finish, n., v.)
    afterward(s)
       afterword
    aging
    aid (n., v.)
    aide
    aide-de-camp
    albumen (egg)
       albumin (chemistry)
    align
    allottee
    all ready (prepared)
       already (previous)
    all right
    altogether (completely)
    all together (collectively)
    aluminum
    ambidextrous
    amoeba
    ampoule
    analog
    analogous
    anemia
    anesthetic
    aneurysm
    anomalous
    anonymous
    antediluvian
    antibiotics (n.)
       antibiotic (adj.)
    anyway (adv.)
    anywise (adv.)
    appall, -ed, -ing
    appareled, -ing
    aquatic
    aqueduct
    archaeology
    arrester
    artifact
    artisan
    ascendance, -ant
    ascent (rise)
       assent (consent)
    assassinate
    athenaeum
    attester
    autogiro
    awhile (for some time)
       a while (a short time)
    ax
    aye
    B
    backward
    baloney (nonsense)
    bologna (sausage)
    bandanna
    bargainer
       bargainor (law)
    baritone
    bark (boat)
    barreled, -ing
    bastille
    bathyscaph
    battalion
    bazaar (event)
    bizarre (strange on absurd)
    behoove
    beneficent
    benefited, -ing
    bettor (wagerer)
    beveled, -ing
    biased, -ing
    blessed
    bloc (group)
       block (grants)
    blond (masc, fem.)
    bluing
    born (birth)
    borne (carried)
    bouillon (soup)
       bullion (metal)
    boulder
    bourgeoisie
    breach (gap)
       breech (lower part)
    brier
    briquet, -ted, -ting
    Britannia
    broadax
    bronco
    brunet (masc, fern.)
    buccaneer
    buncombe
    bunion
    bur
    burned
    bus, bused, buses, busing
    butadiene
    C
    caffeine
    calcareous
    calcimine
    caldron
    calendar
    calender (paper finish)
    caliber
    caliper
    calk (spike)
       caulk (seal)
    calligraphy
    callus (n.)
       callous (adj.)
    calorie
    canceled, -ing
    cancellation
    candor
    canister
    cannot
    canoeing
    cantaloupe
    canvas (cloth)
       canvass (solicit)
    capital (city, money)
       capitol (building)
    carabao (sing., pi.)
    carat (gem weight)
       caret (omission mark)
       karat (gold weight)
    carbureted, -ing
    carburetor
    Caribbean
    caroled, -ing
    carotene
    carrot
    cartilage
    caster (roller)
       castor (oil)
    casual (informal)
       causal (cause)
    catalog, -ed, -ing
    cataloger
    catsup
    caviar
    caviled, -er, -ing
    center
    centipede
    centrifugal
    cesarean
    chairmaned
    chaise longue
    chancellor
    channeled, -ing
    chaperon
    chautauqua
    chauvinism
    chiffonier
    chile con carne
    chili (pepper)
    chiseled, -ing
    chlorophyll
    cigarette
    citable
    cite (quote)
       site (place)
    clamor
    climactic (climax)
       climatic (climate)
    cocaine
    coconut
    cocoon
    coleslaw
    colloquy
    colossal
    combated, -ing
    commenter
       commentor (law)
    commingle
    commiserate
    complement (complete)
    compliment (praise)
    confectionery
    confidant (masc, fem.)
       confident (sure)
    confirmer
       confirmor (law)
    conjurer
    connecter
       connector (road)
    connoisseur
    consecrator
    consensus
    consignor
    consulter
    consummate
    contradicter
    control, -lable, -ling
    converter
    conveyor
    cookie
    cornetist
    corollary
    corvette
    councilor (of council)
       counselor (adviser)
    counseled, -ing
    cozy
    crawfish
    creneled, -ing
    crystaled, -ing
    crystalline
    crystallize
    cudgeled, -ing
    cyclopedia
    czar
    D
    darndest
    debarkation
    decaffeinated
    decalogue
    defense
    deliverer
       deliveror (law)
    demagogue
    demarcation
    dependent
    descendant (n., adj.)
    desecrater
    desiccate
    desuetude (suspended)
    destitute (bereft)
    detractor
    develop, -ment
    device (contrivance)
       devise (convey)
    dextrous (syllable division)
    diaeresis
    diaeretic
       diuretic (water pill)
    diagramed, -ing
    diagrammatic
    dialed, -ing
    dialogue
    dialysis
    diaphragm
    diarrhea
    dickey
    dietitian
    diffuser
    dike
    dilettante
    dinghy (boat)
    diphtheria
    discreet (prudent)
       discrete (distinct)
    disheveled, -ing
    disk
    dispatch
    dissension
    distention
    distill, -ed, -ing, -ment
    distributor
    diverter
    divorcee
    doctoral
    doctrinaire
    doggerel
    dossier
    doweled, -ing
    downward
    dreadnought
    dreamed
    drought
    dueled, -ing
    duffelbag
    dullness
    dumfound
    dwelt
    dyeing (coloring)
       dying (death)
    E
    eastward
    ecstasy
    edema
    edgewise
    electronics (n.)
       electronic (adj.)
    eleemosynary
    elicit (to draw)
       illicit (illegal)
    embarrass
    embed
    embellish
    emboweled, -ing
    emboweler
    emigrant (go from)
       immigrant (go into)
    emigree
    eminent (famous)
       imminent (soon)
    employee
    enameled, -ing
    encage
    encase
    encave
    enclasp
    enclose
    enclosure
    encumber
    encumbrance
    encyclopedia
    endorse, -ment
    endwise
    enfeeble
    enforce, -ment
    engraft
    enroll, -ed, -ing, -ment
    en shade
    en sheathe
    ensnare
    ensure (guarantee)
       insure (protect)
    entrench
    entrepreneur
    entrust
    entwine
    envelop (v.)
       envelope (n.)
    enwrap
    eon
    epaulet, -ed, -ing
    epiglottis
    epilogue
    equaled, -ing
    erysipelas
    escallop
    escapable
    esophagus
    etiology
    evacuee
    evanescent
    eviscerate
    evocative
    exhibitor
    exhilarate
    exonerate
    exorbitant
    expellant
    exposé (n., exposure)
       expose (v., to lay open)
    exsiccate
    extant (in existence)
       extent (range)
    extoll, -ed, -ing
    eying
    eyrie
    F
    fantasy
    farther (distance)
       further (degree)
    favor
    fecal
    feces
    fetal
    fetish
    fetus
    fiber
    fiche (microfiche)
    filigree
    finable
    finagle
    financier
    fjord
    flammable (not inflammable)
    flection
    fledgling
    flexitime
    flier
    flotage
    flotation
    fluorescent
    focused, -ing
    folderal
    forbade
    forbear (endurance)
       forebear (ancestor)
    foresee
    forgettable
    forgo (relinquish)
       forego (precede)
    format, formatted,
       formatting
    forswear
    fortissimo
    forward (ahead)
       foreword (preface)
    fricassee
    fuchsia
    fueler
    fulfill, -ed, -ing, -ment
    fulsome
    fungus (n., adj.)
    funneled, -ing
    furor
    fuse (all meanings)
    fuselage
    fusillade
    G
    gaiety
    gaily
    galosh
    gamboled, -ing
    garrote
    gauge
    gazetteer
    gelatin
    genealogy
    generalissimo
    germane
    glamorous
    glamour
    glycerin
    gobbledygook
    goodbye
    graveled, -ing
    gray
    grievous
    groveled, -ing
    gruesome
    guarantee (n., v.)
       guaranty (n., law)
    guerrilla (warfare)
       gorilla (ape)
    guesstimate
    guttural
    gypsy
    H
    hallelujah
    hara-kiri
    harass
    harebrained
    healthful (for health)
    healthy (with health)
    heinous
    hemoglobin
    hemorrhage
    heterogeneous
    hiccup
    highfalutin
    hijack
    homeopath
    homogeneity
    homologue
    hors d'oeuvre
    hypocrisy
    hypotenuse
    I
    idiosyncrasy
    idle (inactive)
       idol (statue)
    idyll
    imminent (soon)
       eminent (famous)
    impaneled, -ing
    impasse
    imperiled, -ing
    impostor
    impresario
    imprimatur
    inculcate
    indict (to accuse)
       indite (to compose)
    inequity (unfairness)
       iniquity (sin)
    inferable
    infold
    ingenious (skillful)
       ingenuous (simple)
    innocuous
    innuendo
    inoculate
    inquire, inquiry
    install, -ed, -ing, -ment
    installation
    instill, -ed, -ing
    insure (protect)
       ensure (guarantee)
    intelligentsia
    interceptor
    interment (burial)
       internment (jail)
    intern
    intervener
       intervenor (law)
    intransigent (n., adj.)
    iridescent
    italic
    J
    jalopy
    jalousie
    jerry-(built)
       jury- (rigged)
    jeweled, -ing, -er
    jewelry
    judgeship
    judgment
    jujitsu
    juxtaposition
    K
    karat
    kerneled, -ing
    kerosene
    kidnapped, -ing
    kidnapper
    kilogram
    knapsack
    kopek
    kumquat
    L
    labeled, -ing
    lacquer
    landward
    lath (wood)
       lathe (machine)
    laureled
    leukemia
    leveled, -ing
    leveler
    liable (responsible)
       libel (legal)
    liaison
    libelant
    libeled, -ing
    libelee
    libeler
    license
    licenser (issuer)
       licensor (grantor)
    licorice
    likable
    lilliputian
    linage (lines)
       lineage (descent)
    liquefy
    liquor
    liqueur
    liter
    livable
    loath (reluctant)
    loathe (detest)
    lodestar
    lodgment
    lodestone
    logistics (n.)
    logistic (adj.)
    louver
    luster
    lyonnaise
    M
    madam
    Mafia
    maim
    maize (corn)
       maze (labyrinth)
    maneuver
    manifold
    manikin (dwarf)
    mannequin (model)
    mantel (shelf)
       mantle (cloak)
    marbleize
    marijuana
    marshaled, -ing
    marshaler
    marveled, -ing
    marvelous
    material (goods)
       materiel (military)
    meager
    medaled, -ing
    medalist
    medieval
    metaled, -ing
    metalize
    meteorology (weather)
       metrology (weights and measures)
    meter
    mil ($^1$⁄$_{1000}$ inch)
    mill ($^1$⁄$_{1000}$ dollar)
    mileage
    miliary (tuberculosis)
    milieu
    milk cow
    millenary (1,000)
    millinery (hats)
    millennium
    minable
    missilery
    misspell
    miter
    moccasin
    modeled, -ing
    modeler
    mold
    mollusk
    molt
    moneys
    monogramed, -ing
    monologue
    mortise
    movable
    mucilage
    mucus (n.)
       mucous (adj.)
    Muslim
    mustache
    N
    naphtha
    Navajo
    nazism
    neophyte
    niacin
    nickel
    niter
    nonplused
    northward
    Novocain (trademark)
    novocaine (anesthetic)
    numskull
    O
    obbligato
    obloquy
    ocher
    octet
    offal
    offense
    omelet
    ophthalmology
    opossum
    orangutan
    orbited, -ing
    ordinance (law)
       ordnance (military)
    organdy
    overseas or oversea
    P
    pajamas
    paleontology
    paneled, -ing
    paraffin
    paralleled, -ing
    parallelepiped
    parceled, -ing
    partisan
    pastime
    patrol, -led, -ling
    peccadillo
    pedant (n.)
    pedantic (adj.)
    peddler
    penciled, -ing
    pendant (n.)
       pendent (u.m.)
    percent
    peremptory (decisive)
       preemptory (preference)
    perennial
    periled, -ing
    permittee
    perquisite (privilege)
    prerequisite (requirement)
    personal (individual)
    personnel (staff)
    perspective (view)
    prospective (expected)
    petaled, -ing
    pharaoh
    pharmacopeia
    phoenix
    phlegm
    phony
    phosphorus (n.)
       phosphorous (adj.)
    photostated
    pickax
    picnicking
    pipet
    plaque
    plastics (n.)
       plastic (adj.)
    pledger
       pledgor (law)
    plenitude
    pliers
    plow
    poleax
    pollination
    pommeled, -ing
    pontoon
    porcelaneous
    practice (n., v.)
    precedence (priority)
       precedents (usage)
    prerogative
    pretense
    preventive
    principal (chief)
       principle (proposition)
    privilege
    proffer
    programmatic
    programmed, -mer, -ming
    prologue
    promissory
    pronunciation
    propel, -led, -ling
    propellant (n.)
       propellent (adj.)
    prophecy (n.)
       prophesy (v.)
    ptomaine
    pubic (anatomy)
    pulmotor
    pusillanimous
    Q
    quarreled, -ing
    quartet
    quaternary
    questionnaire
    queue
    R
    raccoon
    racket (all meanings)
    rapprochement
    rarefy
    rarity
    ratable
    rational (adj.)
       rationale (n.)
    rattan
    raveled, -ing
    reconnaissance
    reconnoiter
    recyclable
    referable
    refuse
    registrar
    reinforce
    relater
       relator (law)
    remodeler
    renaissance
    reparable
    repellant (n.)
       repellent (adj.)
    requester
       requestor (law)
    rescission
    responder (electronics)
    responser (electronics)
    reveled, -er, -ing
    rhyme, rhythmic
    RIFing, RIFed, RIFs
    rivaled, -ing
    roweled, -ing
    ruble
    S
    saccharin (n.)
       saccharine (adj.)
    sacrilegious
    salable
    sandaled, -ing
    savable
    savanna
    savior
       Saviour (Christ)
    scalloped, -ing
    schizophrenia
    scion (horticulture)
    scurrilous
    seismology
    selvage (edging)
       salvage (save)
    sentineled, -ing
    separate (v., adj.)
    sepulcher
    seriatim
    settler
       settlor (law)
    sewage (waste)
       sewerage (drain system)
    sextet
    Shakespearean
    shellacking
    shoveled, -ing
    shriveled, -ing
    sideward
    signaled, -ing
    siphon
    site (place)
       cite (quote)
    sizable
    skeptic
    skillful
    skulduggery
    sleight (deft)
    slight (meager)
    smolder
    sniveled, -ing
    snorkel
    soliloquy
    sometime (formerly)
       some time (some time ago)
       some times (at times)
    southward
    spacious (space)
       specious (deceptive)
    specter
    spirituous (liquor)
    spirochete
    spoliation
    stationary (fixed)
       stationery (paper)
    statue (sculpture)
       stature (height)
       statute (law)
    staunch
    stenciled, -ing
    stenciler
    stifling
    stratagem
    stubbornness
    stultify
    stupefy
    subpoena, -ed
    subtlety
    succor
    sulfur (also derivatives)
       sulfanilamide
       sulfureted, -ing
    supererogation
    surfeit
    surreptitious
    surveillance
    swiveled, -ing
    sylvan
    synonymous
    syrup
    T
    taboo
    tactician
    tasseled, -ing
    tattoo
    taxied, -ing
    technique
    teetotaler
    tercentenary
    theater
    therefor (for it)
       therefore (for that reason)
    thiamine
    thralldom
    thrash (beat)
       thresh (grain)
    threshold
    tie, tied, tying
    timber (wood)
       timbre (tone)
    tinseled, -ing
    titer
    tonsillitis
    tormenter
    totaled, -ing
    toward
    toweled, -ing
    toxemia
    trafficking
    trammeled, -ing
    tranquilize(r)
    tranquillity
    transcendent
    transferable
    transferor
    transferred
    transonic
    transponder (electronics)
    transshipment
    traveled, -ing
    traveler
    travelogue
    triptych
    trolley
    troop (soldiers)
       troupe (actors)
    troweled, -ing
    tryptophan
    tularemia
    tunneled, -ing
    tunneler
    turquoise
    typify
    tyrannical
    tyro
    U
    unctuous
    unwieldy
    upward
    uremia
    usable
    V
    vacillate
    valance (drape)
       valence (chemistry)
    veld
    veranda
    vermilion
    vicissitude
    victualed, -ing
    victualer
    vilify
    villain
    visa, -ed, -ing
    vitamin
    vitrify
    volcanism
    voluntarism
    votable
    vying
    W
    wainscoting
    warranter
       warrantor (law)
    warranty
    weeviled, -ing
    welder
    westward
    whimsy
    whiskey, -s
    willful
    withe
    woeful
    woolen
    woolly
    worshiped, -er, -ing
    A
    abaca
    aide memoire
    a la carte
    a la king
    a la mode
    angstrom
    aperitif
    applique
    apropos
    auto(s)-da-fe
    B
    blase
    boutonniere
    brassiere
    C
    cabana
    cafe
    cafeteria
    caique
    canape
    cause celebre
    chateau
    cliche
    cloisonne
    comedienne
    comme ci
       comme ca
    communique
    confrere
    consomme
    cortege
    coulee
    coup de grace
    coup d'etat
    coupe
    creme
    crepe
    crepe de chine
    critique
    critiquing
    D
    debacle
    debris
    debut
    debutante
    decollete
    dejeuner
    denouement
    depot
    dos-a-dos
    E
    eclair
    eclat
    ecru
    elan
    elite
    entree
    etude
    F
    facade
    faience
    faux pas
    fete
    fiance (masc, fem.)
    frappe
    G
    garcon
    glace
    grille
    gruyere
    H
    habitue
    I
    ingenue
    J
    jardiniere
    L
    laissez faire
    litterateur
    M
    materiel
    matinee
    melange
    melee
    menage
    mesalliance
    metier
    moire
    N
    naive
    naivete
    nee
    O
    opera bouffe
    opera comique
    P
    papier mache
    piece de resistance
    pleiade
    porte cochere
    porte lumiere
    portiere
    pousse cafe
    premiere
    protege (masc, fem.)
    puree
    R
    rale
    recherche
    regime
    risque
    role
    rotisserie
    roue
    S
    saute
    seance
    senor
    smorgasbord
    soiree
    souffle
    suede
    T
    table d'hote
    tete-a-tete
    tragedienne
    V
    vicuna
    vis-a-vis
    à l'américaine
    attaché
    béton
    blessé
    calèche
    cañada
    cañon
    chargé
    chargé d'affaires
    congé
    crédit foncier
    crédit mobilier
    curé
    déjà vu
    détente
    doña
    entrepôt
    exposé
    longéron
    mañana
    maté
    mère
    nacré
    outré
    passé (masc, fem.)
    pâté
    père
    piña
    précis
    raisonné
    résumé
    touché
    albinos
    armadillos
    avocados
    banjos
    cantos
    cascos
    centos
    didos
    duodecimos
    dynamos
    escudos
    falsettos
    gauchos
    ghettos
    halos
    indigos
    infernos
    juntos
    kimonos
    lassos
    magnetos
    mementos
    merinos
    mestizos
    octavos
    octodecimos
    pianos
    piccolos
    pomelos
    provisos
    quartos
    salvos
    sextodecimos
    sextos
    siroccos
    solos
    tangelos
    tobaccos
    twos
    tyros
    virtuosos
    zeros
When a noun is hyphenated with an adverb or preposition, the plural is formed on the noun.
    comings-in
    fillers-in
    goings-on
    hangers-on
    listeners-in
    lookers-on
    markers-up
    passers-by
    swearers-in
When neither word is a noun, the plural is formed on the last word.
    also-rans
    come-ons
    go-betweens
    higher-ups
    run-ins
    tie-ins
    Significant word first:
       adjutants general
       aides-de-camp
       ambassadors at large
       attorneys at law
       attorneys general
       billets-doux
       bills of fare
       brothers-in-law
       charges d'affaires
       chiefs of staff
       commanders in chief
       comptrollers general
       consuls general
       courts-martial
       crepes suzette
       daughters-in-law
       governors general
       grants-in-aid
       heirs at law
       inspectors general
       men-of-war
       ministers-designate
       mothers-in-law
       notaries public
       pilots-in-command
       postmasters general
       presidents-elect
       prisoners of war
       reductions in force
       rights-of-way
       secretaries general
       sergeants at arms
       sergeants major
       solicitors general
       surgeons general
    Significant word in middle:
       assistant attorneys general
       assistant chiefs of staff
       assistant comptrollers general
       assistant surgeons general
    Significant word last:
       assistant attorneys
       assistant commissioners
       assistant corporation counsels
       assistant directors
       assistant general counsels
       brigadier generals
       deputy judges
       deputy sheriffs
       general counsels
       judge advocates
       judge advocate generals
       lieutenant colonels
       major generals
       provost marshals
       provost marshal generals
       quartermaster generals
       trade unions
       under secretaries
       vice chairmen
       men employees
       secretaries-treasurers
       women aviators
    Both words equally significant:
       Bulletins Nos. 27 and 28 not Bulletin Nos. 27 and 28 but Bulletin No. 27 or 28
       coats of arms
       masters at arms
       men buyers
    No word significant in itself:
       forget-me-nots
       hand-me-downs
       jack-in-the-pulpits
       man-of-the-earths
       pick-me-ups
       will-o'-the-wisps
Nouns ending with ful form the plural by adding s at the end; if it is necessary to express the idea that more than one container was filled, the two elements of the solid compound are printed as separate words and the plural is formed by adding s to the noun.
    five bucketfuls of the mixture (one bucket filled five times)
    five buckets full of earth (separate buckets)
    three cupfuls of flour (one cup filled three times)
    three cups full of coffee (separate cups)
    addendum, addenda
    adieu, adieus
    agendum, agenda
    alga, algae
    alumnus, alumni (masc); alumna, alumnae (fern.)
    antenna, antennas (antennae, zoology)
    appendix, appendixes
    aquarium, aquariums
    automaton, automatons
    axis, axes
    bandeau, bandeaux
    basis, bases
    bateau, bateaux
    beau, beaus
    cactus, cactuses
    calix, calices
    cargo, cargoes
    chassis (singular and plural)
    cherub, cherubs
    cicatrix, cicatrices
    Co., Cos.
    coccus, cocci
    consortium, consortia
    corrigendum, corrigenda
    crisis, crises
    criterion, criteria
    curriculum, curriculums
    datum (singular), data (plural, but singular in collective sense)
    desideratum, desiderata
    dilettante, dilettanti
    dogma, dogmas
    ellipsis, ellipses
    equilibrium, equilibriums (equilibria, scientific)
    erratum, errata
    executrix, executrices
    flambeau, flambeaus
    focus, focuses
    folium, folia
    formula, formulas
    forum, forums
    fungus, fungi
    genius, geniuses
    genus, genera
    gladiolus (singular and plural)
    helix, helices
    hypothesis, hypotheses
    index, indexes (indices, scientific)
    insigne, insignia
    italic (singular and plural)
    Kansas Citys
    lacuna, lacunae
    larva, larvae
    larynx, larynxes
    lens, lenses
    lira, lire
    locus, loci
    madam, mesdames
    Marys
    matrix, matrices
    maximum, maximums
    medium, mediums or media
    memorandum, memorandums
    minimum, minimums
    minutia, minutiae
    monsieur, messieurs
    nucleus, nuclei
    oasis, oases
    octopus, octopuses
    opus, opera
    parenthesis, parentheses
    phenomenon, phenomena
    phylum, phyla
    plateau, plateaus
    podium, podiums
    proces-verbal, proces-verbaux
    radius, radii
    radix, radixes
    referendum, referendums
    sanatorium, sanatoriums
    sanitarium, sanitariums
    septum, septa
    sequela, sequelae
    seraph, seraphs
    seta, setae
    ski, skis
    stadium, stadiums
    stimulus, stimuli
    stratum, strata
    stylus, styluses
    syllabus, syllabuses
    symposium, symposia
    synopsis, synopses
    tableau, tableaus
    taxi, taxis
    terminus, termini
    testatrix, testatrices
    thesaurus, thesauri
    thesis, theses
    thorax, thoraxes
    vertebra, vertebras (vertebrae, zoology)
    virtuoso, virtuosos
    vortex, vortexes
The following words end in ible; other words in this class end in able.
    abhorrible
    accendible
    accessible
    addible
    adducible
    admissible
    appetible
    apprehensible
    audible
    avertible
    bipartible
    circumscriptible
    coctible
    coercible
    cognoscible
    cohesible
    collapsible
    collectible(s)
    combustible
    comestible
    commonsensible
    compactible
    compatible
    competible
    compossible
    comprehensible
    compressible
    conducible
    conductible
    confluxible
    congestible
    contemptible
    controvertible
    conversable (oral)
    conversible
    convertible
    convincible
    corrigible
    corrodible
    corrosible
    corruptible
    credible
    crucible
    cullible
    decoctible
    deducible
    deductible
    defeasible
    defectible
    defensible
    delible
    deprehensible
    depressible
    descendible
    destructible
    diffrangible
    diffusible
    digestible
    dimensible
    discernible
    discerpible
    discerptible
    discussible
    dispersible
    dissectible
    distensible
    distractible
    divertible
    divestible
    divisible
    docible
    edible
    educible
    effectible
    effervescible
    eligible
    eludible
    erodible
    evasible
    eversible
    evincible
    exemptible
    exhaustible
    exigible
    expansible
    explosible
    expressible
    extensible
    fallible
    feasible
    fencible
    flexible
    fluxible
    forcible
    frangible
    fungible
    fusible
    gullible
    horrible
    ignitible
    illegible
    immersible
    immiscible
    impartible
    impatible
    impedible
    imperceptible
    impermissible
    imperscriptible
    impersuasible
    implausible
    impossible
    imprescriptible
    imputrescible
    inaccessible
    inadmissible
    inapprehensible
    inaudible
    incircumscriptible
    incoercible
    incognoscrible
    incombustible
    incommiscible
    incompatible
    incomprehensible
    incompressible
    inconcussible
    incontrovertible
    inconvertible
    inconvincible
    incorrigible
    incorrodible
    incorruptible
    incredible
    indefeasible
    indefectible
    indefensible
    indelible
    indeprehensible
    indestructible
    indigestible
    indiscernible
    indivertible
    indivisible
    indocible
    inducible
    ineffervescible
    ineligible
    ineludible
    inevasible
    inexhaustible
    inexpansible
    inexpressible
    infallible
    infeasible
    inflexible
    infractible
    infrangible
    infusible
    innascible
    inscriptible
    insensible
    instructible (convertible)
    insubmergible
    insuppressible
    insusceptible
    intactible
    intangible
    intelligible
    interconvertible
    interruptible
    intervisible
    invendible
    invertible
    invincible
    invisible
    irascible
    irreducible
    irrefrangible
    irremissible
    irreprehensible
    irrepressible
    irresistible
    irresponsible
    irreversible
    legible
    mandible
    marcescible
    misicible
    negligible
    nexible
    omissible
    ostensible
    partible
    passable (open) ​
    passible (feeling)
    perceptible
    perfectible
    permissible
    persuasible
    pervertible
    plausible
    possible
    prehensible
    prescriptible
    producible
    productible
    protrusible
    putrescible
    receptible
    redemptible
    reducible
    reflectible
    reflexible
    refrangible
    remissible
    renascible
    rendible
    reprehensible
    repressible
    reproducible
    resistible
    responsible
    reversible
    revertible
    risible
    runcible
    sconcible
    seducible
    sensible
    sponsible
    suasible
    subdivisible
    submergible
    submersible
    subvertible
    suggestible
    supersensible
    suppressible
    susceptible
    suspensible
    tangible
    tensible
    terrible
    thurible
    traducible
    transmissible
    transvertible
    tripartible
    unadmissible
    uncorruptible
    unexhaustible
    unexpressible
    unintelligible
    unresponsible
    unsusceptible
    vendible
    vincible
    visible
    vitrescible
A large number of words have the termination ise, ize, or yze. The letter l is followed by yze if the word expresses an idea of loosening or separating, as analyze; all other words of this class, except those ending with the suffix wise and those in the following list, end in ize.
    advertise
    advise
    affranchise
    apprise (to inform)
    apprize (to appraise)
    arise
    chastise
    circumcise
    comprise
    compromise
    demise
    despise
    devise
    disenfranchise
    disfranchise
    disguise
    emprise
    enfranchise
    enterprise
    excise
    exercise
    exorcise
    franchise
    improvise
    incise
    merchandise
    misadvise
    mortise
    premise
    prise (to force)
       prize (to value)
    reprise
    revise
    rise
    supervise
    surmise
    surprise
    televise
A single consonant following a single vowel and ending in a monosyllable or a final accented syllable is doubled before a suffix beginning with a vowel.
    bag, bagging
    format, formatting
    input, inputting
    red, reddish
    rob, robbing
    transfer, transferred
    but
    total, totaled, totaling
    travel, traveled, traveling
If the accent in a derivative falls upon an earlier syllable than it does in the root word, the consonant is not doubled.
    refer, reference
    prefer, preference
    infer, inference
The indefinite article a is used before a consonant and an aspirated h; an is used before a silent h and all vowels except u pronounced as in visual and o pronounced as in one.
    a historic occasion
    a hotel
    a human being
    a humble man
    a union
    an herb seller
    an hour
    an honor
    an onion
    an oyster
    but
    an H-U-D directive
    a HUD directive
When a group of initials begins with b, c, d, g,j, k, p, q, t, u, v, w, y, or z, each having a consonant sound, the indefinite article a is used.
    a BLS compilation
    a CIO finding
    a GAO limitation
    a UFO sighting
    a WWW search
When a group of initials begins with a, e,f, h, i, I, m, n, o, r, s, or x, each having a vowel sound, the indefinite article an is used.
    an AEC report
    an FCC (ef) ruling
    an NSC (en) proclamation
    an RFC (ahr) loan
Use of the indefinite article a or an before a numerical expression is determined by the consonant or vowel sound of the beginning syllable.
    an 11-year-old
    a onetime winner
    a III (three) group
    an VIII (eight) classification
    a IV-F (four ef) category (military draft)
    a 4-H Club
The spelling of geographic names must conform to the decisions of the U.S. Board on Geographic Names (BGN) (http://geonames.usgs.gov). In the absence of such a decision, the U.S. Directory of Post Offices is to be used.
If the decisions or the rules of the BGN permit the use of either the local official form or the conventional English form, it is the prerogative of the originating office to select the form which is most suitable for the matter in hand; therefore, in marking copy or reading proof, it is required only to verify the spelling of the particular form used. GPO's preference is for the conventional English form. Copy will be followed as to accents, but these should be consistent throughout the entire job.
The table on Demonyms in Chapter 17 "Useful Tables" shows forms to be used for nouns and adjectives denoting nationality.
In designating the natives of the States, the following forms will be used.
    Alabamian
    Alaskan
    Arizonan
    Arkansan
    Californian
    Coloradan
    Connecticuter
    Delawarean
    Floridian
    Georgian
    Hawaiian
    Kentuckian
    Idahoan
    Illinoisan
    Indianian
    Iowan
    Kansan
    Louisianian
    Mainer
    Marylander
    Massachusettsan
    Michiganian
    Minnesotan
    Mississippian
    Missourian
    Montanan
    Nebraskan
    Nevadan
    New Hampshirite
    New Jerseyan
    New Mexican
    New Yorker
    North Carolinian
    North Dakotan
    Ohioan
    Oklahoman
    Oregonian
    Pennsylvanian
    Rhode Islander
    South Carolinian
    South Dakotan
    Tennessean
    Texan
    Utahn
    Vermonter
    Virginian
    Washingtonian
    West Virginian
    Wisconsinite
    Wyomingite
Observe the following forms:
    African-American
    Alaska Native (Aleuts, Eskimos, Indians of Alaska)
    Amerindian
    Native American (American Indian)
    Puerto Rican
    Part-Hawaiian (legal status)
but part-Japanese, etc.
Words, including tribal and other proper names of Indian, Aleut, Hawaiian, and other groups, are to be followed literally as to spelling and the use of spaces, hyphens, etc.