UPSTIR is a playable word

upstir Scrabble® Dictionary

verb
upstirred, upstirring, upstirs
to stir up
60 Playable Words can be made from "UPSTIR"
   2-Letter Words (8 found)
   3-Letter Words (23 found)
   4-Letter Words (17 found)
   5-Letter Words (10 found)
   6-Letter Words (2 found)