SAFEST is a playable word

safe Scrabble® Dictionary

adjective
safer, safest
free from danger
(adverb) safely
noun
pl. safes
a metal receptacle for storing valuables
72 Playable Words can be made from "SAFEST"
   2-Letter Words (10 found)
   3-Letter Words (22 found)
   6-Letter Words (3 found)