to·pon·y·my 
(tə-pŏnə-mē)
(tə-pŏnə-mē)n. pl. to·pon·y·mies
1.
a. The place names of a region or language.
b. The study of such place names.
2. Anatomy Nomenclature with respect to a region of the body rather than to organs or structures.
to·pon·y·mist (-mĭst) n.