mouser vs panther

mouser

noun
  • A cat that catches mice, kept specifically for the purpose. 

  • A moustache. 

panther

noun
  • Any big cat of the genus Panthera. 

  • A cougar; especially the Florida panther. 

  • Any of various big cats with black fur; most especially, the black-coated leopard of India. 

  • A girl, especially a young one, who pursues older men. 

  • A creature resembling a big cat with a multicolored hide, found in Ancient Greek mythology. 

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