flack in WordNet English dictionary

1. artillery designed to shoot upward at airplanes
   antiaircraft  antiaircraft gun  flak  flack  pom-pom  ack-ack  ack-ack gun 
   
2. intense adverse criticism
   "Clinton directed his fire at the Republican Party"; "the government has come under attack"; "don't give me any flak"
   fire  attack  flak  flack  blast 
   
3. a slick spokesperson who can turn any criticism to the advantage of their employer
   flak catcher  flak  flack catcher  flack 
   

flack in English Wiktionary