kitten vs leopard

kitten

noun
  • A young cat, especially before sexual maturity (reached at about seven months). 

  • A moth of the genus Furcula. 

  • A young rabbit, rat, hedgehog, squirrel, fox, beaver, badger, etc. 

  • A term of endearment, especially for a woman. 

verb
  • To give birth to kittens. 

leopard

noun
  • A similar-looking, large wild cat named after the leopard. 

  • The snow leopard (Panthera uncia), a large wild cat native to Asia. 

  • A lion passant guardant. 

  • Panthera pardus, a large wild cat with a spotted coat native to Africa and Asia, especially the male of the species (in contrast to leopardess). 

  • Any of various nymphalid butterflies of the genus Phalanta, having black markings on an orange base. 

  • The clouded leopard (Neofelis nebulosa), a large wild cat native to Asia. 

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