Eponym

noun

1. A real or fictitious person's name that has given rise to the name of a particular item.

   "Romulus is the eponym of Rome."

2. A word formed from a real or fictive person’s name.

   "Rome is an eponym of Romulus."

3. (by extension) A word formed from a real or fictive place or thing.

   "“Tangerine” is an eponym of Tangier."