Tibbles vs tortoiseshell

Tibbles

name
  • A surname originating as a patronymic. 

tortoiseshell

noun
  • A domestic cat (or a rabbit, guinea-pig, etc.) whose fur has black, brown and yellow markings. 

  • The hawksbill turtle. 

  • The horny, translucent, mottled covering of the carapace of the hawksbill turtle, used as a veneer etc. 

  • Any of several butterflies, mostly of the genera Nymphalis and Aglais that have similar markings. 

adj
  • Having markings resembling covering of carapace of hawksbill turtle. 

  • Made of the covering of carapace of hawksbill turtle. 

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