The word is fancy.
The opposite for the word plain starting with letter f is FANCY.
Famous?
frowning
Fresh
· fragile · flimsy
Foolish begins with F and it is the opposite of wise.
Famished is a word for extremely hungry that starts with the letter F.
An action word that stars with f is fly!
fluff, fief
Forcast
A five (5) letter word that starts with Z and ends with F, there is none recorded. However, there is a word that starts with Z and ends with F. The word is a four (4) letter word: zarf, (noun) a metal holder for a coffee cup.
Fronto is the only word i know