Words That Start With O — Scrabble & Word Games

O is the 4th most common letter in English at about 7.5%. O is both a vowel and an interjection (OH! O!). It is the most frequently rounded vowel and appears in nearly every English word that has a “long O” or “short O” vowel sound.

In Scrabble, O is worth 1 point with 8 O tiles in the bag. O-initial high-value Scrabble plays include OZONE, OXBOW, OXIDIZE, OBJECT.

Productive O-prefixes: OB- (against — OBJECT, OBSTRUCT), OC- / OF- / OP- (assimilated variants of OB-), OVER- (above, excess — OVERLOAD, OVERCOME), OUT- (beyond — OUTDO, OUTSIDE). OUT- and OVER- alone generate many hundreds of productive compound words. O is critical for bingo building: most 7-letter bingos contain at least one O vowel.

Top 500 Highest-Scoring Words Starting With O (500 of 8,889)

OXYPHENBUTAZONE41
OBJECTIVIZING37
OBJECTIVIZED36
OBJECTIVIZES35
OVEREMPHASIZING35
OBJECTIVIZE34
OOPHORECTOMIZED34
OVEREMPHASIZED34
OVERHOMOGENIZED34
OXYRHYNCHUSES34
OOPHORECTOMIZES33
OVEREMPHASIZES33
OVERHOMOGENIZES33
OXYHAEMOGLOBINS33
OOPHORECTOMIZE32
OPHTHALMOPHOBIA32
OVERADVERTIZING32
OVERCAPITALIZED32
OVEREMPHASIZE32
OVERHOMOGENIZE32
OVERSPECIALIZED32
OXYGENIZING32
OXYHAEMOGLOBIN32
OXYHEMOGLOBINS32
OXYRHYNCHUS32
OXYTETRACYCLINE32
OBJECTIFICATION31
OPHTHALMOSCOPIC31
OPHTHALMOSCOPY31
ORTHOPSYCHIATRY31
OUTDAZZLING31
OVARIECTOMIZED31
OVERADVERTIZED31
OVERCAPITALIZES31
OVERCIVILIZED31
OVERDRAMATIZING31
OVERFERTILIZING31
OVERGLAMORIZING31
OVERSPECIALIZES31
OXYGENIZED31
OXYGENIZERS31
OXYHEMOGLOBIN31
OXYMORONICALLY31
OBJECTIFYING30
OCCIDENTALIZING30
ONYCHOCRYPTOSES30
ONYCHOCRYPTOSIS30
ORTHOPHOSPHORIC30
OUTDAZZLED30
OVERADVERTIZES30
OVERBEJEWELLED30
OVERCAPITALIZE30
OVERCENTRALIZED30
OVERDRAMATIZED30
OVEREQUIPPING30
OVERFERTILIZED30
OVERGLAMORIZED30
OVERSPECIALIZE30
OXYCEPHALIC30
OXYCEPHALY30
OXYGENIZER30
OXYGENIZES30
OXYHYDROGENS30
OZONIZATIONS30
OBJECTIONABLY29
OBJECTIVENESSES29
OBJECTIVISTIC29
OCCIDENTALIZED29
OPHTHALMOMETRY29
OPHTHALMOSCOPES29
ORGANIZABILITY29
ORNITHORHYNCHUS29
ORTHOGONALIZING29
ORTHOPYROXENES29
OUTDAZZLES29
OUTJOCKEYING29
OVERADVERTIZE29
OVERANALYZING29
OVERBEJEWELED29
OVERCENTRALIZES29
OVERDRAMATIZES29
OVEREQUIPPED29
OVEREXCITEMENTS29
OVEREXPECTATION29
OVEREXTRAVAGANT29
OVERFERTILIZES29
OVERGENERALIZED29
OVERGLAMORIZES29
OVERQUALIFIED29
OVERSIMPLIFYING29
OVERWHELMINGLY29
OVERWITHHOLDING29
OVOVIVIPAROUSLY29
OXAZEPAMS29
OXIDIZABLE29
OXIDIZATIONS29
OXYCEPHALIES29
OXYCEPHALOUS29
OXYGENIZE29
OXYHYDROGEN29
OZONIZATION29
OBJECTIVATING28
OBJECTIVATIONS28
OBJECTIVELY28
OBJECTIVISING28
OBJECTIVISMS28
OBJECTIVITY28
OCCIDENTALIZES28
ONYCHOPHAGISTS28
ONYCHOPHAGY28
OPHTHALMOPLEGIA28
OPHTHALMOSCOPE28
OPTIMALIZATIONS28
ORTHOGONALIZED28
ORTHOPHOSPHATES28
ORTHOPYROXENE28
OUTDAZZLE28
OUTJOCKEYED28
OVERACHIEVEMENT28
OVERADJUSTMENTS28
OVERANALYZED28
OVERCENTRALIZE28
OVERDRAMATIZE28
OVEREXAGGERATED28
OVEREXCITEMENT28
OVERFERTILIZE28
OVERGENERALIZES28
OVERGLAMORIZE28
OVERIDEALIZING28
OVERORGANIZING28
OVERZEALOUSLY28
OXAZEPAM28
OXIDIZATION28
OXYACETYLENES28
OXYSULPHIDES28
OZONIZING28
OBJECTIVATED27
OBJECTIVATION27
OBJECTIVENESS27
OBJECTIVISED27
OBJECTIVISM27
OBJECTIVITIES27
OCCIDENTALIZE27
OCHLOCRATICALLY27
OCHLOPHOBIACS27
ODONTORHYNCHOUS27
OESOPHAGOSCOPY27
OLIGOMERIZATION27
OMPHALOSKEPSES27
OMPHALOSKEPSIS27
ONYCHOPHAGIES27
ONYCHOPHAGIST27
OPHTHALMOLOGIC27
OPHTHALMOLOGY27
OPHTHALMOMETERS27
OPISTHOGRAPHIC27
OPISTHOGRAPHY27
OPTIMALIZATION27
ORCHESOGRAPHY27
OROPHARYNXES27
ORTHOCHROMATISM27
ORTHOGONALIZES27
ORTHOPHOSPHATE27
OVERADJUSTMENT27
OVERANALYZES27
OVERCLASSIFYING27
OVERCOMPLEX27
OVERCOMPLICATED27
OVERCONFIDENTLY27
OVEREMPLOYMENTS27
OVEREXAGGERATES27
OVEREXCITABLE27
OVEREXERCISING27
OVEREXPANDING27
OVEREXPLAINING27
OVEREXPLOITING27
OVEREXTRACTIONS27
OVERGENERALIZE27
OVERIDEALIZED27
OVERORGANIZED27
OVERQUICK27
OVERUTILIZATION27
OVERZEALOUSNESS27
OVOVIVIPARITY27
OXIDIZING27
OXYACETYLENE27
OXYSULPHIDE27
OZONIZED27
OZONIZERS27
OBJECTIFIED26
OBJECTIFY26
OBJECTIONABLE26
OBJECTIVATES26
OBJECTIVISES26
OBJECTIVISTS26
OBSEQUIOUSLY26
OCHLOPHOBIAC26
OCHLOPHOBICS26
OFFHANDEDNESSES26
OLIGOCYTHAEMIAS26
OMBUDSMANSHIPS26
OMPHALOMANCY26
ONYCHOMANCY26
ONYCHOPHORANS26
OPHIOMORPHIC26
OPHTHALMOLOGIES26
OPHTHALMOLOGIST26
OPHTHALMOMETER26
OPISTHOBRANCHS26
OPISTHOGNATHISM26
OPISTHOGRAPHIES26
OPTIMALIZING26
OPTIMIZATIONS26
ORCHESOGRAPHIES26
OREOGRAPHICALLY26
ORGANOPHOSPHATE26
ORNITHOMORPHIC26
ORTHOCHROMATIC26
ORTHOGONALIZE26
ORTHOPAEDICALLY26
OUTJOCKEYS26
OVERANALYZE26
OVERCOMMITMENTS26
OVERCOMMUNICATE26
OVERCOMPLIANCES26
OVERCOMPLICATES26
OVERCONFIDENCES26
OVERDEVELOPMENT26
OVEREMBELLISHED26
OVEREMPHASISING26
OVEREMPLOYMENT26
OVEREXAGGERATE26
OVEREXERCISED26
OVEREXPANDED26
OVEREXPANSIONS26
OVEREXPLAINED26
OVEREXPLICIT26
OVEREXPLOITED26
OVEREXTRACTION26
OVERFAMILIARITY26
OVERFLOWINGLY26
OVERGRAZINGS26
OVERIDEALIZES26
OVERIDENTIFYING26
OVERJUMPING26
OVERMULTIPLYING26
OVERORGANIZES26
OVERPACKAGING26
OVERPOWERINGLY26
OVERPRIZING26
OVERPROGRAMMING26
OVERUTILIZING26
OVERWITHHOLDS26
OVOVIVIPARITIES26
OXIDIZED26
OXIDIZERS26
OXIDOREDUCTASES26
OXYPHILIC26
OZONIZER26
OZONIZES26
OZONOSPHERES26
OBJECTIFIES25
OBJECTIVATE25
OBJECTIVISE25
OBJECTIVIST25
OBJECTLESSNESS25
OBSEQUIOUSNESS25
OCEANOGRAPHICAL25
OCHLOPHOBIC25
OESOPHAGOSCOPES25
OFFHANDEDLY25
OFFICEHOLDERS25
OLIGARCHICALLY25
OLIGOCYTHAEMIA25
OMBUDSMANSHIP25
OMNICOMPETENCES25
OMPHALOMANCIES25
ONYCHOMANCIES25
ONYCHOPHORAN25
OOJAMAFLIPS25
OOPHORECTOMISED25
OPHIOMORPHOUS25
OPISTHOBRANCH25
OPTIMALIZED25
OPTIMIZATION25
ORCHIDECTOMY25
ORNITHODELPHIC25
OROGRAPHICALLY25
OROPHARYNX25
ORTHOCEPHALIC25
ORTHOCEPHALY25
ORTHOGRAPHICAL25
ORTHOHYDROGENS25
ORTHOPEDICALLY25
ORTHOPRAXY25
OSTEOPATHICALLY25
OSTRACIZABLE25
OUTJINXING25
OUTJOCKEY25
OVERACHIEVING25
OVERCLOCKINGS25
OVERCOMMITMENT25
OVERCOMPENSATED25
OVERCOMPLIANCE25
OVERCOMPLICATE25
OVERCOMPRESSING25
OVERCONFIDENCE25
OVEREMBELLISHES25
OVEREMPHASISED25
OVEREXCITING25
OVEREXERCISES25
OVEREXPANSION25
OVEREXPOSING25
OVEREXPOSURES25
OVEREXTENDING25
OVEREXUBERANT25
OVERFLOURISHING25
OVERFORWARDNESS25
OVERFREIGHTING25
OVERGLAZING25
OVERGRAZING25
OVERHOMOGENISED25
OVERIDEALIZE25
OVERJUMPED25
OVERORGANIZE25
OVERPACKAGED25
OVERPRESCRIBING25
OVERPRIZED25
OVERPROGRAMMED25
OVERSCHUTCHT25
OVERSIMPLIFIED25
OVERSIMPLIFY25
OVERSUBSCRIBING25
OVERUTILIZED25
OVERWHELMINGS25
OVERWITHHELD25
OVERWITHHOLD25
OXIDATIVELY25
OXIDIZER25
OXIDIZES25
OXIDOREDUCTASE25
OZONIZE25
OZONOSPHERE25
OBJECTIVAL24
OBJECTIVES24
OBJURGATIVE24
OBJURGATORY24
OBLIQUENESSES24
OBNOXIOUSNESSES24
OCHLOPHOBIAS24
OESOPHAGOSCOPE24
OFFENSIVENESSES24
OFFHANDEDNESS24
OFFICEHOLDER24
OKEYDOKEY24
OLIGOSACCHARIDE24
OMNIBENEVOLENCE24
OMNICOMPETENCE24
OMOPLATOSCOPY24
OOJAMAFLIP24
OOPHORECTOMISES24
OOPHORECTOMY24
OPENMOUTHEDLY24
OPHTHALMITISES24
OPISTHOGNATHOUS24
OPISTHOGRAPHS24
OPSONIZATIONS24
OPTIMALIZES24
OPTIMIZING24
ORCHIDECTOMIES24
ORCHIDOMANIACS24
ORGANIZATIONAL24
ORGANOGRAPHICAL24
ORNITHODELPHIAN24
ORNITHODELPHOUS24
ORNITHOPHOBIAS24
OROMAXILLARY24
ORTHOCEPHALIES24
ORTHOCEPHALOUS24
ORTHODONTICALLY24
ORTHODOXLY24
ORTHOHYDROGEN24
ORTHOMORPHIC24
ORTHOPHYRIC24
ORTHOPINAKOIDS24
ORTHOPRAXIES24
ORTHORHOMBIC24
OSCILLOGRAPHIC24
OSCILLOGRAPHY24
OSTEICHTHYANS24
OUTBRAZENING24
OUTFANGTHIEVES24
OUTJINXED24
OUTORGANIZING24
OVERACHIEVED24
OVERACHIEVERS24
OVERAMPLIFIED24
OVERANXIETY24
OVERAPPLICATION24
OVERBLEACHING24
OVERCANOPYING24
OVERCAPACITY24
OVERCHECKS24
OVERCLOCKING24
OVERCOMMITTING24
OVERCOMPENSATES24
OVERCOMPRESSED24
OVERCONSUMPTION24
OVERDEPENDENCES24
OVERDEVELOPING24
OVERDOCUMENTING24
OVEREFFUSIVE24
OVEREMPHASISES24
OVEREMPHATIC24
OVEREQUIPS24
OVEREXCITED24
OVEREXERCISE24
OVEREXPANDS24
OVEREXPLAINS24
OVEREXPLOITS24
OVEREXPOSED24
OVEREXPOSURE24
OVEREXTENDED24
OVEREXTENSIONS24
OVERFLOURISHED24
OVERFULFILLING24
OVERGLAZED24
OVERGRAZED24
OVERHARVESTING24
OVERHOMOGENISES24
OVERIMAGINATIVE24
OVERJOYING24
OVEROFFICING24
OVERPACKAGES24
OVERPESSIMISTIC24
OVERPRESCRIBED24
OVERPRIVILEGED24
OVERPRIZES24
OVERPROTECTIVE24
OVERSENSITIVITY24
OVERSHADOWING24
OVERSIMPLIFIES24
OVERSKIPPING24
OVERSUBSCRIBED24
OVERSUPPLYING24
OVERUTILIZES24
OVERWATCHING24
OVERWEATHERING24
OVERWEIGHTING24
OVERWHELMING24
OVOVIVIPAROUS24
OXAZINES24
OXAZOLES24
OXIDIZE24
OXPECKERS24
OXYMORONIC24
OXYPHILES24
OYSTERCATCHERS24
OZZIES24
OBJECTIVE23
OBLIQUATIONS23
OBLIQUELY23
OBLIQUITY23
OBNOXIOUSLY23
OBSERVABILITY23
OBSERVATIONALLY23
OBSTRUCTIVELY23
OCCUPATIONALLY23
OCEANOGRAPHIC23
OCEANOGRAPHY23
OCHLOPHOBIA23
OFFENSIVELY23
OFFICIALDOMS23
OFFICIOUSNESSES23
OLIGODENDROCYTE23
OMBROPHOBOUS23
OMOPLATOSCOPIES23
ONCHOCERCIASES23
ONCHOCERCIASIS23
OOPHORECTOMIES23
OOPHORECTOMISE23
OPAQUENESSES23
OPENMOUTHEDNESS23
OPERATIZING23
OPHIOMORPHS23
OPHIOPHAGOUS23
OPHIOPHILISTS23
OPISTHOGRAPH23
OPSONIZATION23
OPTIMALIZE23
OPTIMISTICALLY23
OPTIMIZED23
OPTIMIZERS23
ORCHIDOMANIAC23
ORCHIECTOMY23
ORGANIZABLE23
ORGANIZATIONS23
ORIENTALIZING23
ORNITHOMORPHS23
ORNITHOPHILY23

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Frequently Asked Questions

Are there a lot of words that start with O?

There are 8,889 English words in our list that start with O. As a share of the dictionary, that’s around 2.5%. English-wide, O shows up in roughly 7.5% of written text — the 4th most common letter overall.

What's the best O-word to play in Scrabble?

Ranked by Scrabble value, OXYPHENBUTAZONE wins at 41 points. Landing it on a premium square boosts the score further. For reference, the O tile itself contributes 1 point.

What's the smallest word that begins with O?

OB is the shortest O-initial entry we have, at 2 letters. Tiny words like this are bread-and-butter for quick board plays — a single premium-square hit can score high without committing your bingo tiles.