MATRIX is a playable word

matrix Scrabble® Dictionary

noun
pl. matrixes or matrices
something within which something else originates or develops
44 Playable Words can be made from "MATRIX"
   2-Letter Words (11 found)
   3-Letter Words (21 found)
   4-Letter Words (10 found)
   5-Letter Words (1 found)
   6-Letter Words (1 found)