7 Letter Countable Nouns Starting with O

Explore 248 verified English 7 letter countable nouns that start with O, including Opinion, Opening, Officer, Overall, Organic, Outcome and Offense. Browse these count nouns with singular and plural forms below, or review singular and plural count rules in our noun grammar guide.

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Starts with OA9 words
oatmeal
oakwood
oarsman
oarlock
oatcake
oarfish
oakleaf
oakling
oarweed
Starts with OB10 words
oblique
obelisk
obverse
obligor
obscura
obloquy
obligee
obsequy
obliger
obelion
Starts with OC12 words
octopus
octagon
ocarina
oculist
octuple
occiput
octanol
octopod
ocellus
oceanid
octapla
ockodol
Starts with OD7 words
odyssey
oddball
oddness
oddment
odorant
odonate
oddsman
Starts with OE
2 words
oersted
oenomel
Starts with OF11 words
officer
offense
offside
offload
offbeat
offramp
offeror
offtake
offeree
offerer
offcast
Starts with OI7 words
oilseed
oilskin
oilbird
oilfish
oilhole
oilcamp
oidioid
Starts with OK
1 words
okimono
Starts with OL10 words
oldster
olivine
ologist
oloroso
olearia
oldwife
olykoek
oligist
olitory
ologoan
Starts with OM6 words
omicron
omnibus
omakase
omentum
omusubi
omitter
Starts with ON10 words
ongoing
onigiri
onliner
onanist
oncogen
onychia
ondatra
ongchoy
onomast
onstead
Starts with OO4 words
ootheca
oospore
oophyte
oosperm
Starts with OP16 words
opinion
opening
optimum
opacity
opossum
operand
opposer
operant
opaline
oppidum
opuntia
opaleye
oppidan
ophiura
ophites
oporice
Starts with OQ
1 words
oquassa
Starts with OR24 words
organic
orderly
orchard
orbital
orifice
oregano
ordinal
origami
oratory
oration
orbiter
organza
orality
orderer
organdy
organum
orogeny
orebody
ortolan
oralist
orphrey
ordinee
orgiast
oratrix
Starts with OS16 words
ostrich
osmosis
osteoid
osteria
ossuary
ossicle
osteoma
ostmark
ossetra
ostiole
osculum
ostiary
osmunda
osmiate
osselet
osmerid
Starts with OT7 words
ottoman
ottawan
otolith
otalgia
otarine
otocyst
otariid
Starts with OU24 words
outside
outcome
outline
outlook
outrage
outward
outcast
outpost
outflow
outlier
outback
outtake
outplay
outcrop
outwork
outpour
outsize
outshot
outsole
outland
outfall
outcall
outturn
outflux
Starts with OV21 words
overall
overlap
overlay
overrun
ovation
overpay
overage
overbid
overdub
overarm
oviduct
overhit
overdog
overdye
overman
overset
overbet
overcut
ovality
ovicide
ovipara
Starts with OX13 words
oxidant
oxidase
oxalate
oxblood
oxheart
oxyacid
oxyphil
oxazole
oxytone
oxonium
oxazine
oxysalt
oxysome
Starts with OZ
1 words
ozonide

•Browse Countable Nouns by Letter (A to Z)

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