KNAPSACK is a playable word

knapsack Scrabble® Dictionary

noun
pl. knapsacks
a bag carried on the back
63 Playable Words can be made from "KNAPSACK"
   2-Letter Words (6 found)
   3-Letter Words (18 found)
   5-Letter Words (13 found)
   6-Letter Words (1 found)
   8-Letter Words (1 found)