COSECS is a playable word

cosec Scrabble® Dictionary

noun
pl. cosecs
cosecant
23 Playable Words can be made from "COSECS"
   2-Letter Words (4 found)
   3-Letter Words (8 found)
   4-Letter Words (5 found)
   5-Letter Words (4 found)
   6-Letter Words (2 found)