UNHAPPEN is a playable word

unhappen Scrabble® Dictionary

verb
unhappened, unhappening, unhappens
to become as though never having happened
58 Playable Words can be made from "UNHAPPEN"
   2-Letter Words (15 found)
   3-Letter Words (25 found)
   4-Letter Words (9 found)
   5-Letter Words (6 found)
   6-Letter Words (2 found)
   8-Letter Words (1 found)