What is Beefing?

Beefing definition and meaning on Dictionary terms:
noun, plural beeves [beevz] /bivz/ for 2; beefs for 4.
the flesh of a cow, steer, or bull raised and killed for its meat.
an adult cow, steer, or bull raised for its meat.
Informal. brawn; muscular strength. strength; power. weight, as of a person. human flesh.

Slang. a complaint. an argument or dispute.

verb (used without object)
Slang. to complain; grumble.

Verb Phrases
beef up, to add strength, numbers, force, etc., to; strengthen: During the riots, the nighttime patrol force was beefed up with volunteers. to increase or add to: to beef up our fringe benefits.