fight back
phrasal verbfight back (against somebody/something) 
- to resist strongly or attack somebody who has attacked you
- Don't let them bully you. Fight back!
 - It is time to fight back against street crime.
 - Collins fought back to level the match at two sets all.
 
 
fight something  back/down 
- to try hard not to do or show something, especially not to show your feelings
- I was fighting back the tears.
 - He fought down his disgust.