the.com/beef

means As a noun, a complaint or grudge against someone ("I've got a beef with you"); its plural "beefs" as cattle-flesh is "beeves."

from The meat sense comes straight from Old French buef/boef (ox, beef cattle), itself from Latin bos — the same root that gives us 'bovine.' The grudge sense is murkier: 19th-century American slang, possibly from criminal/hobo argot where 'beef' meant a complaint or an accusation to police, maybe linked to 'hot beef' as old slang for shouting 'stop thief.' Nobody can prove the exact leap from cow to complaint — but by the late 1800s, 'beef' as grievance was already common American slang, and it's stuck ever since.