epithet

epithet, adjective or phrase that is used to express a characteristic of a person or thing, such as Ivan the Terrible. In literature, the term is considered an element of poetic diction, something that distinguishes the language of poetry from ordinary language. Homer used certain epithets so regularly that they became a standard part of the name of the thing or person described, as in “rosy-fingered Dawn” and “gray-eyed Athena.” The device was used by many later poets, including John Keats in his sonnet “On First Looking into Chapman’s Homer”:

Oft of one wide expanse had I been told
That deep-browed Homer ruled as his demesne.