mordancy vs venom

mordancy

noun
  • The state or quality of being mordant. 

venom

noun
  • Feeling or speech marked by spite or malice; vitriol. 

  • An animal toxin intended for offensive use, a biological poison delivered by bite, sting, etc. to protect an animal or to kill its prey. 

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