epithet

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A term used to characterize a person or thing, such as rosy-fingered in rosy-fingered dawn or the Great in Catherine the Great.
2. n. A term used as a descriptive substitute for the name or title of a person, such as The Great Emancipator for Abraham Lincoln.
3. n. An abusive or contemptuous word or phrase.
4. n. Biology A word in the scientific name of an animal or plant following the name of the genus and denoting a species, variety, or other division of the genus, as sativa in Lactuca sativa.

Century Dictionary and Cyclopedia

1. n. An adjective, or a word or phrase used as an adjective, expressing some real quality of the person or thing to which it is applied, or attributing some quality or character to the person or thing: as, a benevolent or a hard-hearted man; a scandalous exhibition; sphinx-like mystery; a Fabian policy.
2. n. Hence In rhetoric, a term added to impart strength or ornament to diction, and differing from an adjective in that it designates as well as qualifies, and may take the form of a surname: as, Dionysius the Tyrant; Alexander the Great.
3. n. A phrase; an expression.
4. To entitle; describe by epithets.

Wiktionary

1. n. A term used to characterize a person or thing.
2. n. A term used as a descriptive substitute for the name or title of a person.
3. n. An abusive or contemptuous word or phrase.
4. n. 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.

GNU Webster's 1913

1. n. An adjective expressing some quality, attribute, or relation, that is properly or specially appropriate to a person or thing.
2. n. Term; expression; phrase.
3. v. To describe by an epithet.

WordNet 3.0

1. n. a defamatory or abusive word or phrase
2. n. descriptive word or phrase