1. verb To physically attack someone, as with punches and other blows, such that they suffer significant injury. In this usage, a noun or pronoun can be used between "beat" and "up." The captain of the football team swore he would beat me up if I ever talked to his girlfriend again. I can't believe that skinny kid beat up the school bully!

2. verb To defeat an opponent easily and/or by a wide margin. In this usage, the phrase is often followed by "on." The final score was 17-1? Wow, we really beat up on that team! I got beat up by a much more highly ranked opponent in the first round.

3. verb To criticize someone harshly and/or continually. In this usage, the phrase is often followed by "on." Mom, I know you're disappointed in Stephanie's grades, but quit beating up on her—she feels bad enough as it is. I haven't made many sales this year, so I expect to get beat up in my performance review.

4. verb To damage or wear out from heavy use. I'm afraid I tend to beat up my shoes really quickly.

5. adjective Showing signs of wear or damage, as from heavy use. The phrase is typically hyphenated before a noun. Can we throw away these beat-up old notebooks already? The old car looks really beat up, but it runs pretty well.