Garand Thumb 

When the operator of an M1 Garand get's his thumb smooshed by the bolt as he loads a clip into the rifle.

Jon's finger was purple from a bad case of garand thumb.

Garand Thumb by Heyitsj000 July 15, 2020

grand theft auto thumb 

In most grand theft auto games, a lot of cheats include left down right up left down right up. On an xbox or ps2 controller, you can slide your thumb across the directional pad to put these buttons in. If you do this too many times, you'll wear the skin off of your thumb.

Video gamer 1: Hey, wanna play Halo 2?
Gamer 2: No, I have a bad case of Grand Theft Auto Thumb.

grand theft auto thumb by C_D_XXX May 23, 2007

garandthumb 

Gigachad of the gun world

Bro, you're just like garandthumb!

garandthumb by Nancywheeler March 20, 2023