The ungratifying sexual action of plugging the female genitals with a thumb to stop bleeding.
Came about when Kentucky Ballistics, the Pro-Gun Youtuber, had an accident in which his firearm exploded and lacerated his jugular to which Mr. Kentucky then plugged his otherwise fatal accident with his thumb.
A form of erotic asphyxiation, in which someone uses the dominant thumb to jab into the throat of a partner (or self) to cut breathing and gain sexual arousal.
Also see Kentucky Thumb in the Bum: when a person inserts a thumb into their partners anus during scat play, to plug the flow of feces.
My relationship with Courtney has never been more alive ever since I gave her the ol KentuckyThumb.