WHOOSIS is a playable word

whoosis Scrabble® Dictionary

noun
pl. whoosises
an object or person whose name is not known
45 Playable Words can be made from "WHOOSIS"
   2-Letter Words (11 found)
   3-Letter Words (15 found)
   4-Letter Words (11 found)
   5-Letter Words (5 found)
   6-Letter Words (2 found)
   7-Letter Words (1 found)