impactogenic
Having an impact origin; due to a collision with a comet, meteor, asteroid, or other astronomical body.

impactual
Of or relating to an impact.

impairable
Able to be impaired.

impalatable
unpalatable

impalpable
Incapable of being touched or felt; incorporeal, intangible.
Not able to be perceived, or able to be perceived only with difficulty; insubstantial, thin.
Not easily grasped (mentally) or understood.

impanate
To embody in bread, especially in the bread of the Eucharist.

impapyrated
Written or recorded on or as if on papyrus.

imparasyllabic
Misspelling of imparisyllabic.

imparidigitate
Having an odd number of fingers or toes.

imparipinnate
pinnate with a single leaflet at the apex

imparisyllabic
Not having the same number of syllables in all its inflections (especially of Greek or Latin nouns); for example, the Latin word pars, which has the genitive form partis.

imparisyllabics
plural of imparisyllabic

imparous
Having never given birth.

imparsable
unparsable; not parsable; that cannot be parsed.

imparsimonious
Not parsimonious.

impartable
Capable of being imparted.

impartial
treating all parties, rivals, or disputants equally; not partial; not biased

impartible
not partible; not subject to partition; indivisible

imparticipable
Not participable.

impartite
undivided

impartive
Serving to impart something.

impassable
Incapable of being passed over, crossed, or negotiated.
Incapable of being overcome or surmounted.
Not usable as legal tender.

impassible
Unable to feel emotion; impassive.
Incapable of suffering detriment or injury.
Unable to suffer, or feel pain.
Misspelling of impassable.

impassionable
Excitable or sensitive or susceptible to strong emotion.

impassionate
Filled with passion; impassioned

impassioned
Filled with intense emotion or passion; fervent.

impassive
Having, or revealing, no emotion.
Still or motionless.

impatent
Not patent: not open; as
Not patent: not open; as:

impaternate
Fatherless; having been born through parthenogenesis.

impatriotic
Synonym of unpatriotic.

impeachable
Able to be impeached (of a person).
That warrants impeachment (of an offence).

impeachmentworthy
Deserving impeachment, or (of an act) of such character as to warrant impeachment.

impeachy
Relating to impeachment.

impeccable
Perfect, without faults, flaws or errors
Incapable of wrongdoing or sin; immaculate

impeccant
Without sin; impeccable

impectinate
Not pectinate.

impecuniary
impecunious

impecunious
Lacking money.

impedable
Alternative form of impedible.

impedancemetric
Relating to impedancemetry.

impedentiometric
Relating to the measurement of impedance

impedible
Capable of being impeded or hindered.

impedient
Serving to make a marriage illicit but valid.

impedimental
Of the nature of an impediment; hindering or obstructing.

impedimentary
Related to, or of the nature of, an impediment.

impedimented
impeded; afflicted with an impediment

impedimetric
Relating to the measurement of impedance.

impeditive
Causing or being a hindrance; impeding.

impellent
Having the quality of being impelling.

impellents
plural of impellent

impendent
impending; threatening

impenetrable
Not penetrable.
Opaque; obscure; not translucent or transparent.
Incomprehensible; fathomless; inscrutable.

impenitent
Not penitent; specifically (Christianity), not repenting of one's sins; unrepentant.

impennous
Lacking wings.

imperant
commanding

imperated
Alternative form of imperate.

imperatival
Of or pertaining to the imperative mood.

imperative
Essential; crucial; extremely important.
Of, or relating to the imperative mood.
Having semantics that incorporates mutable variables.
Expressing a command; authoritatively or absolutely directive.

imperatives
plural of imperative

imperceivable
that cannot be perceived; imperceptible

imperceived
Not perceived; unperceived.

imperceptive
Unable to perceive.

impercipient
Lacking perception; unable to perceive.

imperf
Abbreviation of imperfect.
Clipping of imperforate or imperforated.

imperfectable
Alternative spelling of imperfectible.

imperfected
simple past and past participle of imperfect

imperfecter
comparative form of imperfect: more imperfect

imperfectest
superlative form of imperfect: most imperfect

imperfectible
Incapable of perfecting.

imperfectionist
Satisfied with imperfection.

imperfectionists
plural of imperfectionist

imperfective
Of, relating to or having the properties of the imperfective aspect.

imperfectives
plural of imperfective

imperforable
incapable of being perforated

imperforate
Not perforated.
Not perforated.

imperforated
Not perforated; having no opening or aperture; imperforate.

imperforates
plural of imperforate

imperfs
plural of imperf

imperialist
Of, or relating to imperialism.

imperialistic
Of or pertaining to imperialism or imperialists; favoring imperialism.

imperialists
plural of imperialist

imperical
Misspelling of empirical.

imperiled
at risk of becoming extinct

imperilled
simple past and past participle of imperil; alternative spelling of imperiled.

imperishable
Not perishable; not subject to decay; enduring permanently.

imperishables
plural of imperishable

impermanent
not permanent; unperpetual.

impermeable
Impossible to permeate.
Not allowing passage, especially of liquids; waterproof.

impermeant
That cannot permeate through a specified semipermeable membrane

impermissible
Not permissible; not to be permitted or allowed.

impermissive
Not permissive.

impermutable
Not permutable.

impers
Abbreviation of impersonal.

imperscriptable
Unrecorded anywhere.

impersistent
Not persistent; fleeting

impersonable
Not personable.

impersonalistic
Of or relating to impersonalism.

impersonative
That impersonates.

impersonatory
That impersonates.

imperspirable
Not perspirable.

impersuadable
Synonym of impersuasible.

impersuasible
Not persuasible; not to be moved by persuasion.

imperturbated
Not perturbated.

imperturbed
Synonym of unperturbed.

impervertible
Unable to be perverted.

imperviable
impervious

impervious
Unaffected or unable to be affected by something.
Preventive of any penetration; impenetrable, impermeable, particularly of water.
Immune to damage or effect.

impetiginized
Accompanied by impetigo.

impetiginous
Of, pertaining to, or suffering from, impetigo.

impetrate
To obtain by asking; to procure upon request.
To ask for, demand.

impetuous
Making arbitrary decisions, especially in an impulsive and forceful manner.
Characterized by sudden violence or vehemence.

impf
Abbreviation of imperfect.
Abbreviation of imperfective.

impingent
Striking against or upon; impinging.

impious
Not pious.
Lacking reverence or respect, especially towards a god.

impire
Obsolete form of empire.

impires
plural of impire

impish
Mischievous; of or befitting an imp.

implacable
Not able to be placated or appeased.
Impossible to prevent or stop; inexorable, unrelenting, unstoppable.
Adamant; immovable.

implacentate
Not placentate; lacking a placenta.

implantational
Relating to implantation

implantological
Relating to implantology.

implastic
Not malleable or flexible.

implausible
Not plausible; unlikely; dubious.

impleadable
inexcusable; not able to plead or excuse

implementable
Able to be implemented.

implemental
Pertaining to, or characterized by, implements or their use; mechanical.

implementary
implementing; relating to implementation of a scheme etc.

implementational
That implements
Of or pertaining to implementation

implementative
Relating to implementation

implementiferous
Yielding implements.

implex
Intricate, involved, entangled, complicated, complex.

implicable
Synonym of impliable (“capable of being implied”).

implicational
Of or pertaining to logical implication.

implicationary
Synonym of implicational.

implicative
Tending to implicate or to imply; pertaining to implication.

implicatory
Relating to implication.

implied
Suggested without being stated directly; implicated or hinted at.