There are no common synonyms that start with O. Some suggestions:
orchidaceous / ostentatious (gaudy, showy)
overwhelming / overpowering (irresistable)
The word ogleable (watchable, attractive) seems to exist only informally.
Outstanding.
obnoxious, obese, obtuse
type in words that start with O it will give you lots of words that start with O and just put it in a list!
Some words that start with the letter O are:oceanOddOdeofoffOfficeogreoldOliveOnoneOpalOppositeorOrangeorboreganoorganismorgasmorigamiotherotteroughtOxymoronoval
Very few words start with o. Famous word aum starts with a but not o.
obvious,octogon,octopus,off,on,october lots of words that start with an "o"
Math words that start with o are operation, order, octagon,ordinary,and more to come!
Some happy words that start with O include: Overjoyed Optimistic Open-hearted
free from danger
Outstanding is a beautiful word. It begins with the letter o.optimistic
Orbit and ozone are space words. They begin with the letter o.
Some words that start with the letter O are, orange, old and Organ. There is also open, olive and order.