Linguistics
In linguistics, an epithet can only be a metaphor, essentially a reduced or condensed use of apposition. Epithets are sometimes attached to a person's name or appear in place of their name, as what might be described as a glorified nickname or sobriquet. An epithet is linked to its noun by long-established usage and some are not otherwise employed. Not every adjective is an epithet. An epithet is especially recognizable when its function is largely decorative, such as if "cloud-gathering Zeus" is employed other than in reference to conjuring up a storm. "The epithets are decorative insofar as they are neither essential to the immediate context nor modelled especially for it. Among other things, they are extremely helpful to fill out a half-verse", Walter Burkert has noted.
Some epithets are known by the Latin term epitheton necessarium because they are required to distinguish the bearers, e.g. as an alternative to ordinals after a prince's name — such as Richard the Lionheart (Richard I of England), or Charles the Fat alongside Charles the Bald. The same epithet can be used repeatedly, in different spheres of life and/or joined to different names, e.g. Alexander the Great as well as Catherine the Great.
Other epithets can easily be omitted without serious risk of confusion, and are therefore known (again in Latin) as epitheton ornans; thus the classical Roman author Virgil systematically called his main hero pius Aeneas, the epithet being pius, which means religiously observant, humble and wholesome, as well as calling the armsbearer of Aeneas fidus Achates, the epithet being fidus, which means faithful or loyal.
There are also specific types of epithets, such as the kenning which appears in works such as Beowulf. An example of a kenning would be the term whale-road, meaning "sea".
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