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

third knuckle shuffle 

1. The act of sexually arousing a female by completely inserting one (or more) fingers into her vagina, i.e. the third knuckle.

2. The act of sexually arousing a man by the use of the hand, i.e. handjob.

1. When I went to drop off Suzie last night she started blowing me and she squirted all over my leather seats doing the third knuckle shuffle!

2. Maria and I were watching TV, and she wouldn't let me get into her panties but she did the third knuckle shuffle on me.

third knuckle shuffle by Tom Thamuz September 1, 2003