obnoxious?
another word for chasm that begins with o omission opening oversight
Obliging is a synonym for obedient. It begins with O.
outdo
orchestrate is an active word that begins with the letter O
A word meaning to leave out which begins with an "o" is omit.
Ophidian. It can also be used as an adjective, as in "ophidian eyes" or "an ophidian coolness."
it begins with the letter o. but if you are french, it begins with a letter o.
Bombs are overpowering and destructive. The adjective begins with the letter O.
overdo
Outside?
Offend is a synonym for the word hurt. It begins with the letter O.
One-half is a hyphenated word. It begins with the letter O.