plain
The opposite for the word plain starting with letter f is FANCY.
A five letter word that is the opposite of the word "gradual" and contains a second letter of "l" is a popular word game answer. The five letter word being sought is "fleet."
Plain is the opposite of fancy.
Fancy.
A five letter word for the opposite of lower is upper.
A five letter word meaning the opposite of hurry would be dally. There may well be others
least
front
night
Sharp
awake
Happy.