TESTIEST is a playable word

testy Scrabble® Dictionary

adjective
testier, testiest
irritable
47 Playable Words can be made from "TESTIEST"
   2-Letter Words (7 found)
   3-Letter Words (14 found)
   4-Letter Words (15 found)
   5-Letter Words (6 found)
   6-Letter Words (4 found)
   8-Letter Words (1 found)