STEMMIEST is a playable word

stemmy Scrabble® Dictionary

adjective
stemmier, stemmiest
abounding in stems
118 Playable Words can be made from "STEMMIEST"
   2-Letter Words (11 found)
   3-Letter Words (22 found)
   7-Letter Words (4 found)
   8-Letter Words (1 found)
   9-Letter Words (1 found)