Only one Ohio
O-HI-O
a red-eyed vireo is a bird that ends in "o"
to.....
Buffalo is not really an antelope, but it is the closest relative to the antelope where the name ends with an o.
Amoeba
· echo
mosquito
Avocado
An Italian company name that begins with "R" and ends with "o" is Roncato.
overdo
Coho salmon which is also known as silver salmon.