COOLDOWN is a playable word

cooldown Scrabble® Dictionary

noun
pl. cooldowns
a gradual return of physiological functions to normal levels after strenuous exercise
46 Playable Words can be made from "COOLDOWN"
   2-Letter Words (7 found)
   3-Letter Words (20 found)
   4-Letter Words (14 found)
   5-Letter Words (4 found)
   8-Letter Words (1 found)