Swalowtail or Swallowtail: How To spell?
The word Swalowtail is misspelled against Swallowtail, a noun meaning "A kind of tenon or tongue used in making joints. See Dovetail."
Swallowtail has double "ll" is mispronounced as "l"Remember double 'LL' in between the strings swa & owtail which should not be misspelled with single 'L'
Wrong Spelling:  swa-l-owtail  Correct Spelling:  swa-ll-owtail 
Find more incorrect spellings of Swallowtail to spell right way.