Bysi or Byssi: How To spell?
The word Bysi is misspelled against Byssi, which is plural of "Byssus"
Byssi has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings by & i which should not be misspelled with single 'S'
Wrong Spelling:  by-s-i  Correct Spelling:  by-ss-i 
Find more wrongly spelled words of Byssi to spell it well.