Oatmeal, offhand, offshoot, online, otherwise, outdoor, outfield, outfit, outgrow, outlaw, outlet, outlook, outnumber, outpatient, outside, overboard, overcoat, overdose, overdue and overuse are compound words. They begin with the letter o.
orchestrate is an active word that begins with the letter O
it begins with the letter o. but if you are french, it begins with a letter o.
One-half is a hyphenated word. It begins with the letter O.
onlyonceomenopenomitoverontoovidovum
overdo
Bombs are overpowering and destructive. The adjective begins with the letter O.
off
Outside?
Outstanding is a nice word. It begins with the letter O.
Offensive is a synonym for horrible. It begins with the letter O.
The word is onslaught.
overwhelmingoverwroughtoutstanding