pigeon pea vs vegetable

pigeon pea

noun
  • The edible seed of this plant. 

  • A tropical African plant, Cajanus cajan, formerly Cajanus indicus. 

vegetable

noun
  • The edible part of such a plant. 

  • A person whose brain (or, infrequently, body) has been damaged so that they cannot interact with the surrounding environment; a person in a persistent vegetative state. 

  • Any plant. 

  • A plant raised for some edible part of it, such as the leaves, roots, fruit or flowers, but excluding any plant considered to be a fruit, grain, herb, or spice in the culinary sense. 

adj
  • Of or relating to plants. 

  • Of or relating to vegetables. 

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