COMPLEXEST is a playable word

complex Scrabble® Dictionary

adjective
complexer, complexest
complicated
verb
complexed, complexing, complexes
to make complex
335 Playable Words can be made from "COMPLEXEST"
   2-Letter Words (18 found)
   8-Letter Words (3 found)
   9-Letter Words (2 found)
   10-Letter Words (1 found)