A aggressive dude with too much testosterone in his system. Usually found bullying others or being overly loud and aggressive while watching sporting events. Often, but not necessarily, seen wearing sports paraphernalia.
1.
Dude: YEAHHHHHH!! WOO! WOOOOO! YEAHHHHHHH!

Rick: Geez, does that guy have to overreact to every play? I almost jumped out of my skin! It's not even a first down for Christ's sake!

Maggie: Testo-boy.

2.
Vagrant: Hey! City boy! You probably voted for Bush didn't you? Hey! I'm talking to you asshole!

Scott (under his breath to Mary): Testo-boy.

Mary: Don't make eye contact.
by ocius1 November 4, 2009
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