FIBERS is a playable word

fiber Scrabble® Dictionary

noun
pl. fibers
a thread or threadlike object or structure
(adjective) fibered
66 Playable Words can be made from "FIBERS"
   2-Letter Words (10 found)
   3-Letter Words (22 found)
   4-Letter Words (19 found)
   5-Letter Words (12 found)
   6-Letter Words (3 found)