epithet vs key word

epithet

noun
  • A word in the scientific name of a taxon following the name of the genus or species. This applies only to formal names of plants, fungi and bacteria. In formal names of animals the corresponding term is the specific name. 

  • A term used as a qualifier of the name of a deity in order to designate said deity in a particular aspect or role. 

  • One of many formulaic words or phrases used in the Iliad and Odyssey to characterize a person, a group of people, or a thing. 

  • A term used to characterize a person or thing. 

  • A term used as a descriptive substitute for the name or title of a person. 

  • An abusive or contemptuous word or phrase. 

verb
  • To term; to refer to as. 

key word

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