Definitions by freechinballs

third knuckle 

When one inserts his fingers in girls anus, stimulating her with each knuckle that penetrates her.

While I was hitting it from the back, I tried the third knuckle to see if she was wit it. And dat bitch came hella hard. It was like Nigeria fall on my balls.

third knuckle by freechinballs September 30, 2017