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1.
A MAN. A meatmountain. He gets REAL physical!
Hey little mama, tell your girlfriend to come over here and meet my friend ______. He is a real beefcastle.
by DuckDuckLoose November 18, 2011
 
2.
One who truly lifts.... A beef castle is huge beyond huge. Spending all free time in the gym, lifting, running, and generally becoming huge. A beef castle will typically have every major muscle in the body showing with less than 5 percent body fat. They also must be able to do exercises such as the muscle up and the human flagpole that normal humans cannot do.
Nicole McVey is the ultimate beef castle. She lifts hard core
by huge lifter dude October 09, 2014