Means: A problem or personal grudge, often resulting in physical aggression.
Usage "What's the beef?""You want beef with me, Darren?"
A pupil borrowing another pupil's calculator without asking? That's a mere argument. Persistently stealing another pupil's maths supplies to the detriment of their grades and incurring the wrath of their mother? That's serious beef. Thought to derive either from cockney rhyming slang for grief ("roast beef") or that said fall-out could result in someone being "dead meat", "beef" is an age-old term again gaining popularity due to its prominence in the hip-hop and grime music scenes. But with its poster boys being Nineties gangsta rappers such as 2Pac and Notorious BIG (who both ended up dead, coincidentally, by the time they were 25) and Dizzee Rascal (who, despite his current clean-cut image, got stabbed for his troubles once upon a time), it's perhaps not a term to take lightly, depending on how leafy your surroundings.