An eponym is the name of a person or thing, whether real or fictitious, after which a particular place, tribe

Ethnonym

An ethnonym is the name applied to a given ethnic group. Ethnonyms can be divided into two categories: exonyms and autonyms or endonyms .As an example, the ethnonym for...

, era

Regnal year

A regnal year is a year of the reign of a sovereign, from the Latin regnum meaning kingdom, rule.The oldest dating systems were in regnal years, and considered the date as an ordinal, not a cardinal number. For example, a monarch could have a first year of rule, a second year of rule, a third, and...

, discovery, or other item is named or thought to be named. One who is referred to as eponymous is someone who gives his or her name to something, e.g., Julian, the eponymous owner of the famous restaurant Julian's Castle. A common nonstandard usage is that something eponymous is named after a particular person, e.g., Julian's eponymous restaurant.

In contemporary English, the term self-titled is often used to mean eponymous in the case of a work with the same name as the person or persons who created it (e.g., the song "Black Sabbath

Black Sabbath (song)

"Black Sabbath" is a song by British heavy metal band of the same name, written in 1969 and released on the band's debut album, Black Sabbath...

", from the album Black Sabbath

Black Sabbath (album)

Black Sabbath is the debut studio album by English heavy metal band Black Sabbath. Released on 13 February 1970 in the United Kingdom, and later on 1 June 1970 in the United States, the album reached number eight on the UK Albums Chart and has been recognised as the first main album to be credited...

, by the band Black Sabbath

Black Sabbath

Black Sabbath are an English heavy metal band, formed in Aston, Birmingham in 1969 by Ozzy Osbourne , Tony Iommi , Geezer Butler , and Bill Ward . The band has since experienced multiple line-up changes, with Tony Iommi the only constant presence in the band through the years. A total of 22...

).

An etiological myth can be a "reverse eponym" in the sense that a legendary character is invented in order to explain a term.