pest vs true bug

pest

noun
  • Any destructive insect that attacks crops or livestock; an agricultural pest. 

  • An animal regarded as a nuisance, destructive, or a parasite, vermin. 

  • An annoying person, a nuisance. 

  • An invasive weed. 

true bug

noun
  • Any of various insects of the order Hemiptera and in particular of the suborder Heteroptera, that are wingless or have two pairs of wings, and have mouthparts adapted for piercing and sucking. 

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