look up any word, like bae:
 
1.
high, wasted
Did you get tresbien last night?
by Brian K. Boviligactic January 27, 2004
 
2.
something that is moybueno.
i.e. good, fashionable, or anything along those lines.
Emily: Whoa, your jacket is moybueno.
Diana: It's totally tresbien.
by Gagalita May 17, 2010
 
3.
a woman who is really a dude.

could be a woman with a penis who likes women, or just a woman who can mentally relate to guys (lesbian or not).

also spelled tresbian
that chick is hot! too bad she's a tresbien.
by NatP January 10, 2008