Oscar’s, Oliver, Omar, Otto, Olaf, Orion, Oakley
Ohio begins with the letter O. Oklahoma and Oregon begin with the letter O.
Orach, orchid
Otto comes to mind.
Orange Ichneumonid wasp and owl moth are insects. They begin with the letter o.
Ocean Perch and Oregon Chub are fish. They begin with the letter O.
There is only one current country beginning with the letter "O"... Oman.
Old Navy and OshKosh B'Gosh are clothing brands. They begin with the letter O.
Oboe and olives are objects. Oranges and ostrich begin with the letter o.
Outstanding and optimistic are positive words. They begin with the letter o.
Oceanography and optometry are college subjects. They begin with the letter o.
Oranges, olives and okra are fruits. They begin 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.