Oceans
ocean
Oklahokma and Ohio
Utah, USA
optimus prime
ouch...
Oregon, Ocean City, Ohio, Orlando,etc. -:D
Do you mean what Norse god starts with o? Odin is a Norse go that starts with O.
Omoo is the Melville tale that starts with O.
A machine that starts with O is an oscillating fan.
an octopus is a simple machine that starts with a o
Oman is the only country that starts with O.