A night owl perched in a tree.
- an owl active chiefly at night
- ☆ a person who works at night or otherwise stays up late
A person who habitually stays up and is active late into the night.
(plural night owls)
- (idiomatic) One who stays up late at night or goes to bed late.
- He's a night owl. He would rather stay up until 6am than wake up at that time.