The crease on the front-side of a t-shirt caused by the wearer's erected nipples, in which the nipples are so hard that the fabric is pulled taut, resulting in a noticeable space between the crease and the wearer's body, much like a long tent.
Dude, I am so cold right now.

Yeah I can tell. You're pitching a nipple tent like 3 inches high!

Hey, did you watch pop idol last night?

Yeah! Did you see Simon Cowell's nipple tent?

How could I not?
by theomnippletentmaster January 7, 2013
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