Eponymous
From our UK edition
Eponymous should be an unusual word, like haplology or apotropaic, used in a narrow semantic field. Yet it is all over the place, in the press and on the lips of media talkers. Properly, it applies to someone who gives his name to anything, especially, the OED notes, ‘the mythical personages from whose names the names of places or peoples are reputed to be derived’. In writing that definition, the lexicographer no doubt had in mind the dictionary’s earliest illustrative quotation of the word, from 1846: ‘The eponymous personage from whom the community derive their name.’ That was from the immensely influential History of Greece by George Grote (1794-1871).