look up any word, like dirty sanchez:
 
1.
They Suck Big Time
a: i like fish fingers
b: TSBT
by thevortex March 16, 2009
 
2.
Acronym for the shirt before the shirt, a phrase made famous by the boys of Jersey Shore.
Before you wear your club shirt, you wear tsbts.
by Miss Potato Head October 17, 2010