Scott you put your question in geology category. If so, kupovity vrch - kupa (pahorek, kopec, vrch ) s pudorysem kruhovym, eliptickym nebo i mirne nepravidelnym.

Vrch (hill) - vypukly tvar reliefu vetsich rozmeru s reletivni vyskou nad urovni okolniho terenu 150-300 m. If so, from "Comprehensive maps of West African schools " by G.K.Erbynn (google books) I found the best and very close def. of: a hill- a small area of land rising higher than the land surrounding it. It is lower than mountain. There are different types of hill -for example, knolls, conical hill, round-topped hills and irregular hills.
A knoll is a small rounded mound or hill which is very often isolated.
A conical hill(s) looks like a cone and is very regular in shape, with a wide base and small top.
Pls. find some pictures on internet, keywording esp. conical hill(s).