Countable Nouns Starting with U and Containing O

Browse 342 valid English countable nouns starting with U and containing O, from Unknown, Underground, Uniform, Upload, Unfortunate, Unlock and Undo to rarer terms. Check definitions and spelling below, or visit our noun grammar guide to review singular and plural count rules.

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Starts with UB
2 words
ubiquitination
ubiquinone
Starts with UD
2 words
udo
udometer
Starts with UF
2 words
ufo
ufologist
Starts with UG
1 words
uglification
Starts with UL24 words
ultrasound
ultranationalist
ultraconservative
ultramarathon
ulceration
ultramarathoner
ultraportable
ultracompact
ululation
ultrafiltration
ultramontane
ultraroyalist
ulyanov
ultracentrifugation
ultrasonogram
ultramodernist
ultrareactionary
ultraspecialization
ultisol
ultimogeniture
ultramicrotome
ultramontanist
ulluco
ultrarevolutionary
Starts with UM4 words
umeboshi
umbo
umbilication
umbonation
Starts with UN24 words
union
unknown
underground
uniform
unfortunate
unlock
undo
underscore
unification
uniformity
underworld
unison
unicorn
underdog
untouchable
undoing
unfollow
unionization
unionist
unlockable
unboxing
undertone
underperformance
underrepresentation
Starts with UP24 words
upload
uptown
upfront
uproar
upshot
upvote
uptempo
updo
upsilon
upholder
upholsterer
upstroke
upcountry
upslope
upgradation
upflow
upgrowth
uptowner
uprootal
upbow
upo
upperworks
upfold
uprooter
Starts with UR24 words
urination
urologist
urokinase
uromastyx
urostomy
urogynecologist
urolithiasis
urethroscopy
urogram
uropod
urolith
urethroscope
urobilin
uricosuric
urochordate
urodele
urson
urography
urbanologist
ureterocystostomy
uricotelic
urinometer
urinoscopy
urosome
Starts with US5 words
usurpation
usucapion
usucaption
ustion
ustulation
Starts with UT11 words
utilization
utopian
utopia
utopianism
utopist
utilidor
uterectomy
uterogestation
uterotomy
utopianizer
utopiast
Starts with UV
1 words
uvulopalatopharyngoplasty
Starts with UX
2 words
uxoricide
uxorilocality
Starts with UZ
1 words
uzboy

•Browse Countable Nouns by Letter (A to Z)

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ABCDEFGHIJKLMNOPQRSTUVWXYZ
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