Casock or Cassock: How To spell?
The word Casock is misspelled against Cassock, a noun meaning "A garment resembling a long frock coat worn by the clergy of certain churches when officiating, and by others as the usually outer garment."
Cassock has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings ca & ock which should not be misspelled with single 'S'
Wrong Spelling:  ca-s-ock  Correct Spelling:  ca-ss-ock 
Find more incorrect spellings of Cassock to spell right way.