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1.
a gay beast
Dude that guy mehdi is a geast.
Ohh yeah man he gives me the shivers!!
Muhhuhuhh
by the_pathan April 24, 2010
 
2.
Pronounced /dʒist/ "jeest."

Noun. A portmanteau of "G", and "Beast." Literally refers to a beast that is a G.

Verb. To beat down in a sexually dominant fashion.

Derivatives:
Adv. Geastily
Adj. Geastly
Dude, Auron is a geast!

He claims to never lose at this video game, but last week he was geasted into submission.

Did you see that fool faceplant? Geastly!
by grassmudhorse April 03, 2009
 
3.
combination of a beast and a geek
After scouring the waiver wire for some holds that helped solidify my spot a top my fantasy league I realized I might be the biggest Geast of all time.
by tgrizzle2007 June 29, 2009