WordNet Dictionary- [n] a name derived from the name of person (real or imaginary) as the name of Alexandria is derived from the name of its founder: Alexander the Great
- [n] the name of a person for whom something is supposedly named; "Constantine I is the eponym for Constantinople"
Webster's 1913 Dictionary\Ep"o*nym\, Eponyme \Ep"o*nyme\, n. [Cf. F. ['e]ponyme.
See {Eponymous}.]
1. The hypothetical individual who is assumed as the person
from whom any race, city, etc., took its name; as, Hellen
is an eponym of the Hellenes.
2. A name, as of a people, country, and the like, derived
from that of an individual.