When you grinding with a girl and you get a full on erection and you flip your dick onto the girls back, as if it were riding it like a horse.
1st Bro: Yeah dudelast night i T-bone'd Lauren and Morgan
2nd Bro: What??
1st Bro: Yeah i just swung my hand down and lifted my schlong onto her back it was nice.
2nd Bro: Nice
A nickname that sounds cool at first, but later a person realizes why that person is so nicknamed. Especially applicable if that person did something stupid to receive said nickname.
Hey have you met T-bone
No, but cool nickname Actually he walked into a parked car.
Wow that is a T-bone.