Toponymy is, by definition, the place names of a particular region and the study of those place names. It is derived, in fact, from the two Greek words topos – meaning place and onoma – meaning name. A toponymist will look at not only the surface meaning of the name in question, but also at the history of the area.
Toponymy is a new word to me. I like the idea behind it. What writer doesn’t love words and word lore and history?