Beefin it 

Beefin it is when a tank ass (fat guy or girl)walks by and you hear there fat legs rubbing together.

Damn girl did you see that guy, he was totally beefin it...

Beefin it by Cambria D.H. September 20, 2005

beefin' it up

1- gaining significant muscle mass
2- the act of drinking protein shakes, then hollaring "YEAH BEEF IT UP" , one may also do a series of push ups after drink has been chugged.
3- increasing anything in large amounts

Ouch, I was beefin' it up yesturday and I think I'm sick. YEAH BEEF IT UP!

beefin' it up by snuffalufagus December 24, 2007

Beefin' it out 

1: rough housing with the boys
2: pooping

1: The dogs had a great time at the park. They had a good time beefin' it out with each other.
2: Sorry bro, I know you're in the shower but is it cool if I take a squat and beef it out real quick?

Beefin' it out by Shady Alleghenys December 2, 2018