gang up on

gang up on or gang up against  {v. phr.},  {informal}
To jointly attack someone, either physically or verbally; take sides in a group against an individual.
The class bully was stronger than all the other boys, so they had to gang up on him to put him in his place.
Compare: LINE UP (4b).
Categories: {informal} {v. phr.}

'gang up on' on video