The point wherein excessive use of a Blackberry or video game controller results in lactic acid build-up in the thumb, and therefore pain and numbness.
His excessive texting resulted in a rather painful bout of BTS - Blackberry Thumb Syndrome, which actually needed prescription pain medication to remedy.
by Daryl Christie October 24, 2008

when you see a bad definition that has a number of thumbs down and 1 thumb up or 1 thumb up alone.
see 1 thumb down or one thumb up
see 1 thumb down or one thumb up
by babtothebone October 23, 2010

by MadSlick August 7, 2017

When you jam your thumb up a ladies poop hole then split her vaginal lips with your index and middle fingers and throw her to the bed.
Okay Rocco after take her ass to pound town get, her in a thumb-under, two-seamer and toss her to the bed.
by Okay Rocco January 9, 2014

The thumb and middle finger pose can be used in things such as photos and videos, and may also be used to identify other people who, much like yourself, have a small penis.
by Canaynay May 25, 2022

When a man fingers their partners anus with his thumb while either self stimulating or having vaginal intercourse to the point of ejaculation, when the thumb is removed and the anus is covered in ejaculate. Named for the appearance and method of baking a thumb print cookie.
by Luck O’ the Irish August 26, 2019

by Barry Lloyd August 10, 2005
