EYE
The word is "envelope" (which usually holds only one letter).
eye
In English, you is the only one.
'Reticulum' is the only one.
There is only one word that starts with the letter E an and with a V. This word is elov.
Ironwood is the only one I know of
an envelope
Only one country starts with the letter O, which is Oman.
Only one. It starts at one end and ends at the other.
monotheis, the worship of only one god
only one - 'xis' which is the 14th letter of the Greek alphabet
One country starts with the letter "O", Oman