barque vs swallowtail

barque

noun
  • A sailing vessel of three or more masts, with all masts but the sternmost square-rigged, the sternmost being fore-and-aft-rigged 

  • A sailing vessel or boat of any kind. 

swallowtail

noun
  • A type of tailcoat with two long tapering tails.ᵂᵖ 

  • The forked tail of a swallow. 

  • Anything, such as a burgee, of a similar forked shape. 

  • Any of various butterflies of the family Papilionidae, many of which have a long extension to each hindwing. 

How often have the words barque and swallowtail occurred in a corpus of books? (source: Google Ngram Viewer )