colter vs petiole

colter

noun
  • The part of a seed drill that makes the furrow for the seed. 

  • A knife or cutter attached to the beam of a plow to cut the sward, in advance of the plowshare and moldboard. 

petiole

noun
  • The stalk of a leaf, attaching the blade to the stem. 

  • A narrow or constricted segment of the body of an insect; especially, the metasomal segment of certain Hymenoptera, such as wasps. 

  • The stalk at the base of the nest of the paper wasp. 

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