Look up peen in Wiktionary, the free dictionary.
Peen may refer to:
- Part of the head of a hammer, as in a ball-peen hammer (also ball-pein, or ball and pein)
- Peening, the changing of a metal's properties by impacting its surface
- Shot peening, bombarding metal parts with small spherical media
- Laser peening, focusing lasers on the surface of a metal part
- Peening (scythe blade), peening a scythe or sickle blade as a step in sharpening it
- Steel Belt: Shot Peening, an innovative remedial solution for deformed steel belts
- A slang term for the penis