Literally "like a bean," but due to the 'fab' nature of the word, it can be used as an adjective for something cute or fabulous. Could also be used as an interjection.
This shirt is fabaceous! Score!

Danny, you are looking so unfabaceous today.

I just had sex! Fabaceous!
by Pavaal January 13, 2011
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(F)ake
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(C)unt
"She wouldn't come get food with me. She was being such a fabac"
by QUEPAQUEENS April 10, 2017
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