instar vs nymph

instar

noun
  • Any one of the several stages of postembryonic development which an arthropod undergoes, between molts, before it reaches sexual maturity. 

  • An arthropod at a specified one of these stages of development. 

  • A stage in development. 

verb
  • To make a star of; set as a star. 

nymph

noun
  • The larva of certain insects. 

  • Any female nature spirit associated with water, forests, grotto, wind, etc. 

  • Any of various butterflies of the family Nymphalidae. 

  • A young girl, especially one who is attractive, beautiful or graceful. 

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