TETRIS is a playable word

tetri Scrabble® Dictionary

noun
pl. tetris
a monetary unit of the Republic of Georgia
61 Playable Words can be made from "TETRIS"
   2-Letter Words (9 found)
   3-Letter Words (18 found)
   4-Letter Words (19 found)
   5-Letter Words (10 found)
   6-Letter Words (5 found)