What is the term for any word or phrase applied to a person or thing that describes a quality?

The term that refers to any word or phrase applied to a person or thing that describes a particular quality is "epithet." An epithet serves to highlight specific traits or characteristics, often embodying an essential aspect of the subject it refers to. For example, in literature and poetry, epithets are frequently used to convey attributes that enhance a character's description, such as "swift-footed Achilles" or "the clear-eyed Athena." This descriptive nature distinguishes epithets from other terms, which may not capture the nuance of quality or characteristic associated with the subject. Understanding the application of epithets deepens comprehension of character development in writing and their role in emphasizing traits in both spoken and written language.