achene vs lentil

achene

noun
  • A small, dry, indehiscent fruit, containing a single seed, as in the buttercup. 

lentil

noun
  • The seed of these plants, used as food. 

  • Any of several plants of the genus Lens, especially Lens culinaris, from southwest Asia, that have edible, lens-shaped seeds within flattened pods. 

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