According to Vocabulary.com, flack is a noun that means “intense adverse criticism.”
Notice that flack is often used with the transitive verb give.
It can also be used with the verb take.
For more examples:
If someone gives you flack about wearing shorts in the winter, tell them to chill out. Flack is a criticism. Flack also refers to anti-aircraft guns, and then sometimes it’s spelled flak.
Photo by Dollar Gill on Unsplash