doggo vs invertebrate

doggo

noun

  • A dog. 

adv

  • Only used in lie doggo. 

invertebrate

noun

  • An animal without vertebrae, i.e. backbone. 

  • A spineless person; a coward. 

adj

  • Cowardly, uncourageous; lacking character. 

  • Lacking a backbone; without vertebrae. 

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