EPONYME

Ep"o*nym, Ep"o*nyme, n. Etym: [Cf. F. éponyme. 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.

Source: Webster’s Unabridged Dictionary 1913 Edition