CESIUM is a playable word

cesium Scrabble® Dictionary

noun
pl. cesiums
a metallic element
46 Playable Words can be made from "CESIUM"
   2-Letter Words (9 found)
   3-Letter Words (19 found)
   4-Letter Words (13 found)
   5-Letter Words (3 found)
   6-Letter Words (2 found)