Geezer is a term for a man. In North America, it carries the connotation of an old person.
Geezer may also refer to:
- Geezer Butler, the founding bassist for Black Sabbath
- GZR, one of three different names used by Geezer Butler's heavy metal band
- Kieran McGeeney, manager of the Kildare senior football team
- A character in the British comic The Beezer
- A small water heater, usually located near the place where hot water is needed.