oaf
obese
objectionable
oblivious (aka "clueless")
obscene
obsequious
obsessed
obsolete
obstructionist
obtuse
obnoxious
obstinate
odious
odoriferous
"off"
offish
offensive
officious
ogre
oily
old
old-fashioned
onanistic (aka "wanker")
onerous
opaque (as opposed to transparent or open)
opportunistic (when used to imply one is taking advantage of someone)
oppressive
ornery
orthodox (when used to imply inflexibility, lack of imagination, or old-fashioned)
orwellian (in reference to the dystopian societies described by George Orwell)
oscillating (when referring to someone who vacillates or flip-flops)
ossified (similar to suggesting someone is a fossil or unable to change)
ototoxic (damaging to the ears - a nasty thing to say about a speaker or singer)
outclassed
oudated
outlandish
outre
outspoken
overambitious
overanxious (you worry too much...)
overbearing
overblown (not as cool as you think you are)
overbold
overcautious
overconfident
overcredulous (what a sucker!)
overcritical
overcurious (aka nosy)
overdelicate (wimp)
overdone
overdressed
overemotional
overenthusiastic
overexcited
overfamiliar (too chummy)
overfed (fat)
overgrown
overheated
overmodest
overreaching
overripe (ever heard of soap?)
oversexed (horn-dog, nympho)
overstuffeed
overzealous
Outstanding and optimistic are positive words. They begin with the letter o.
Oceanography and optometry are college subjects. They begin with the letter o.
Odds are a value. It begins with the letter O.
Several four letter words begin with the letter q. However, there are no four letter words that begin with the letter q and end with the letter o.
outstanding
Outstanding and optimistic are positive words. They begin with the letter o.
Some things that begin with the letter O:outhouseoctopusoptometristopalOscarorangeoak treesoliveoctagonovalovariesorangutanopportunitesoccupied territory
Oceanography and optometry are college subjects. They begin with the letter o.
Odds are a value. It begins with the letter O.
There are no cities in Scotland that begin with the letter O. However, Oban is a town in Scotland.
Oryx
otis
ofoffonontooppositeoutsideover
OctopusOyster
outstanding
odometer
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