GRUMPS is a playable word

grump Scrabble® Dictionary

verb
grumped, grumping, grumps
to complain
35 Playable Words can be made from "GRUMPS"
   2-Letter Words (4 found)
   3-Letter Words (14 found)
   4-Letter Words (13 found)
   5-Letter Words (3 found)
   6-Letter Words (1 found)