Outstanding and optimistic are positive words. They begin with the letter o.
Orbit and ozone are space words. They begin with the letter o.
oh
agoallegroalsoaltoarmadilloaudio
· osmosis
omnipotent
scientific
Obese and oddball are insulting words. They begin with the letter o.
There are all these other scientific Ph words but these are just a few:PharaohPharmacistPharmacyPhilanthropistPhilosopherPhonedPhonePhonicsPhotographPhotographyPhotosynthesisPhysical
Ovary ?
On and Of
oy