ocelloid
a cellular structure found in unicellular microorganisms that is analogous in structure and function to eyes, which focus, process and detect light

ocelloids
plural of ocelloid

ochava
A traditional Spanish unit of mass, equivalent to about 3.6 g.

ochdamh
An obsolete Scots unit equal to ¹⁄₈ daugh, notionally comprising 50 Scottish acres.

ochdamhs
plural of ochdamh

ochem
Alternative form of O-chem.

ochlagogy
Manipulation of a mob by use of inflammatory rhetoric, casting opprobrium, and by appeal to the lowest common denominator generally; extreme and wholly unscrupulous demagogy; the practice of an ochlagogue.

ochlocracies
plural of ochlocracy

ochlocracy
Mob rule; government by the masses; mobocracy.

ochlology
the psychology of crowds or mobs

ochlophilia
A love of crowds or crowded places

ochrept
A particular type of inceptisol.

ochrepts
plural of ochrept

ocivity
Alternative form of oisivity.

ockerdom
The world or sphere of ockers (boorish, uncultivated Australians).

ockerism
The manners or habits of ockers.

ockerisms
plural of ockerism

ocracies
plural of ocracy

ocracy
Any of various forms of government or rule as designated by words ending in -ocracy.

octachlorobiphenyl
Either of twelve isomers of the polychlorinated biphenyl containing eight chlorine atoms

octachlorobiphenyls
plural of octachlorobiphenyl

octachora
plural of octachoron

octachoron
A four-dimensional object analogous to a cube, constructed out of eight cubes.

octachorons
plural of octachoron

octachotomies
plural of octachotomy

octachotomy
The division of one into eight separate but related parts.

octacontagon
A polygon with 80 sides and 80 angles.

octacontagons
plural of octacontagon

octad
A group of eight things.
hundred million = myriad myriad; 100,000,000 = 10⁸

octadecagon
A polygon with 18 sides and 18 vertices.

octadecagons
plural of octadecagon

octadecahedra
plural of octadecahedron

octadecahedron
A polyhedron with eighteen faces.

octadecahedrons
plural of octadecahedron

octadecane
Any of very many isomeric alkanes having the formula C₁₈H₃₈, but especially n-octadecane CH₃(CH₂)₁₆CH₃.

octadecanes
plural of octadecane

octadecene
Any of very many isomers of an alkene having eighteen carbon atoms and one double bond

octadecenes
plural of octadecene

octadiene
Any of several isomeric dienes having eight carbon atoms

octadienes
plural of octadiene

octads
plural of octad

octaedron
Alternative spelling of octahedron.

octafinal
The round in eliminations preceding the quarterfinal round; in single-elimination playoffs, this is the round of 16.
A heat in the octafinal round; in single-elimination tournament play, one of 8 heats.

octagon
A polygon with eight sides and eight angles.
Often in the form Octagon: the arena for mixed martial arts.

octagons
plural of octagon

octagram
An eight-sided star polygon.

octagrams
plural of octagram

octahedra
plural of octahedron

octahedrality
The state or condition of being octahedral.

octahedron
a polyhedron with eight faces; the regular octahedron has regular triangles as faces and is one of the Platonic solids.

octahedrons
plural of octahedron

octakaidecahedron
Synonym of octadecahedron.

octakishexahedron
A polyhedron with 48 faces.

octalogue
A series of eight statements.

octalogues
plural of octalogue

octamerisation
Alternative form of octamerization.

octamerism
The condition of being octamerous

octamerization
oligomerization that forms an octamer

octamethylcyclotetrasiloxane
A particular cyclic siloxane.

octamethyltrisiloxane
A particular linear siloxane.

octanedione
Any of several isomeric diketones, derived from octane, that are used as intermediates in organic synthesis

octanediones
plural of octanedione

octangle
A geometric figure with eight corners, an octagon.

octangles
plural of octangle

octant
The eighth part of a circle; an arc of 45 degrees.
The aspect of two planets that are 45°, or one-eighth of a circle, apart.
The eighth part of a disc; a sector of 45 degrees; half a quadrant.
An instrument for measuring angles, particularly of elevation.

octants
plural of octant

octaoxygen
A red allotrope of oxygen, O₈, that is stable only under very high pressures

octaploidy
Alternative form of octoploidy.

octarchies
plural of octarchy

octarchy
A group of eight states.
A government of eight people.

octaroon
Alternative spelling of octoroon.

octaroons
plural of octaroon

octasome
Any one of eight homologous chromosomes in an aneuploid complement

octasulfur
The most common allotrope of sulfur (S₈), containing eight atoms in a ring.

octatriene
Any of several isomeric trienes having eight carbon atoms

octatrienes
plural of octatriene

octavalence
The property of being octavalent.

octavalency
The condition of being octavalent

octaword
Misspelling of octoword.

octennia
plural of octennium

octennium
An eight-year period.

octenniums
plural of octennium

octenyl
Any of several isomeric radicals derived from an octene

octenyls
plural of octenyl

octeract
An eight-dimensional hypercube

octeracts
plural of octeract

octet
A group or set of eight of something.
A group of eight musicians performing together.
A composition for such a group of musicians.
A byte of eight bits. Abbreviation: o
A group of three bits, representing any of eight possible values.

octets
plural of octet

octett
Alternative spelling of octet.

octetts
plural of octett

octiamond
A polyiamond made up of eight triangles.

octiamonds
plural of octiamond

octile
Any of the quantiles that divide an ordered sample population into eight equally numerous subsets.
A subset thus obtained.
An octant.

octiles
plural of octile

octlet
A word (or rather, a doubleword) consisting of eight bytes (64 bits)

octlets
plural of octlet

octoad
Synonym of ogdoad (“a thing made up of eight parts”).

octoads
plural of octoad

octofinal
Alternative form of octafinal.

octofinals
plural of octofinal

octogamy
The state of having eight spouses simultaneously.

octogenarianism
The state or condition of being an octogenarian.

octogon
Obsolete form of octagon.

octogons
plural of octogon

octogram
A regular eight-pointed star shape.

octograms
plural of octogram

octohedra
plural of octohedron

octohedron
Alternative form of octahedron.

octohedrons
plural of octohedron

octomino
A polyomino consisting of eight squares.

octominoes
plural of octomino

octonionics
The application of the mathematics of octonions in various branches of physics

octophobia
The irrational fear of the number eight.

octoploidization
Modification to become octoploid

octoploidizations
plural of octoploidization

octoploidy
The condition of being octoploid

octoword
A numerical value of eight times the magnitude of a word, 128 bits on a 16-bit architecture.

octowords
plural of octoword

octroi
A privilege granted by the sovereign authority, such as the exclusive right of trade granted to a guild or society; a concession.
A tax levied in money or kind at the gate of a French city on articles brought within the walls.

octrois
plural of octroi

octuplet
A group of eight things, particularly
A group of eight things, particularly
A group of eight things, particularly

octuplets
plural of octuplet

octuplication
multiplication by eight

octupolarity
The condition of being an octupole

octylation
modification by addition of an octyl group

octylations
plural of octylation

octylphenol
A type of alkylphenol.

octylphenols
plural of octylphenol

octyne
Any of many isomeric alkynes having eight carbon atoms and one triple bond

octynes
plural of octyne

ocularcentrism
The privileging of vision over the other senses.

oculism
ophthalmology; optometry

oculodynia
pain in the eye

oculography
The measurement and recording of the position and movement of the eye

oculogyration
Movement of the eye about the anteroposterior axis; eye-rolling

oculogyrations
plural of oculogyration

oculogyria
The rotation of the eyeballs within their orbits.