The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.

eponym

SYLLABICATION: ep·o·nym

PRONUNCIATION: epe-nim

NOUN:
1. A person whose name is or is thought to be the source of the name of something, such as a city, country, or era. For example, Romulus is the eponym of Rome.
2. Medicine A name of a drug, structure, or disease based on or derived from the name of a person.

ETYMOLOGY:
French éponyme, from Greek eponumos, named after : epi-, epi- + onoma, onuma, name; see no-men- in Appendix I.

OTHER FORMS:
ep'o·nym'ic —ADJECTIVE