ROOTKIT is a playable word

rootkit Scrabble® Dictionary

noun
pl. rootkits
software that allows a person to secretly access a computer
40 Playable Words can be made from "ROOTKIT"
   2-Letter Words (7 found)
   3-Letter Words (14 found)
   4-Letter Words (16 found)
   5-Letter Words (2 found)
   7-Letter Words (1 found)