Used almost exclusively attributively (before a noun); seldom, if ever, used predicatively.
He was given a lesser role in the play.
Ему дали незначительную роль в пьесе.
The lesser-known artist finally gained recognition.
Менее известный художник наконец получил признание.
Usually occurs in fixed expressions (e.g., "the lesser of two evils"); countable when pluralized.