byword

noun5

1. •
   A proverb or proverbial expression, common saying; a frequently used word or phrase.
2. •
   Someone or something that stands as an example (i.e. metonymically) for something else, by having some of that something's characteristic traits.
3. •
   An object of notoriety or contempt, scorn or derision.

   • He hath made me also a byword of the people […] — 1611
4. •
   A characteristic word or expression; a word or phrase associated with a person or group.
5. •
   A nickname or epithet.