black(something)up
phrasal verbwithblackverb[T]uk/blæk/us/blæk/
toweardarkmake-upoverpaleskininordertolooklike ablackpersonor tohideyourface:
Whitepeopleused toblackup,mimicusoffensively, and make millions.
The men wouldblackuptheirfaceswithcorkfornightraids.