arum vs arum lily

arum

noun
  • A flower or plant in the genus Arum 

arum lily

noun
  • Any of several flowering plants, of the family Araceae, but especially Zantedeschia aethiopica, the calla lily that has a showy white spathe. 

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