FLATLINED is a playable word

flatline Scrabble® Dictionary

verb
flatlined, flatlining, flatlines
to register as having no brain waves or heartbeat
297 Playable Words can be made from "FLATLINED"
   2-Letter Words (26 found)
   7-Letter Words (6 found)
   8-Letter Words (2 found)
   9-Letter Words (1 found)