bedbug vs chinch

bedbug

noun
  • A small nocturnal insect (Cimex lectularius), of the family Cimicidae, that feeds on the blood of humans and other warm-blooded hosts. 

chinch

noun
  • The bedbug (Cimex lectularius). 

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