buttons vs cobra lily

buttons

noun
  • A small South African plant of the genus Conophytum, with button-like succulent leaves covering its exterior. 

  • Synonym of marbles (“sanity; mental faculties”) 

  • The dung of sheep. 

  • A remote control. 

  • A policeman. 

cobra lily

noun
  • The plant Chasmanthe aethiopica. 

  • Any plant in the genus Arisaema spread in eastern Asia, eastern Africa and eastern North America 

  • A carnivorous plant native to northern California and southern Oregon, Darlingtonia californica 

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