bag on (one)
1. To judge or criticize one. Why are you bagging on me? I didn't do anything wrong! If my friends see me with this stupid haircut, they'll bag on me for months!
2. To tease one. Ugh, my brothers always bag on me when my mom's not around. It's so annoying.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
bag on someone
Sl. to criticize someone. Stop bagging on me! I'm tired of all your complaining. If you are going to bag on everyone all the time, I don't want to hear about it.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.