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1.
To beast it up, is to engage in beastification, or do something that is beast.
Can also be a general phrase indicating thanks or acceptance.
1.You beasted that right up!

2."Have a beer!"
"Beast it up!"

3."Do you wanna beast up a beef?"
"Beast it up!"

4. I just beasted up a fat beefter and now i'm beasted!
by ChunkyMonkey9 October 07, 2006