byword

noun

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