When a penis is fully erect and feels realy hard like a plank of wood.
Renee- "OMG Theo you have an extremely big hard penis! it feels so amazing inside me" ☺
by Likeabossbitch May 14, 2016
Men or women who prefer more than one hard throbbing cock in their life
All she’s been thinking about are a whole bunch of hard penis’s
by Bend over and take it raw February 11, 2021
When a man sees something attractive

Example:
Anything that involves women + r34
Bro I had a hard penis when watching a sextape
by Your average microwave March 18, 2022