molehill vs mound

molehill and mound both are nouns.

Word	Noun	Adjective	Verb	Adverb
molehill	Yes	No	No	No
mound	Yes	No	Yes	No

As nouns, mound is a hypernym of molehill; that is, mound is a word with a broader meaning than molehill:

Other hypernyms of molehill include hammock, hillock, hummock, knoll.

molehill (noun)	mound (noun)
a mound of earth made by moles while burrowing	the position on a baseball team of the player who throws the ball for a batter to try to hit
	structure consisting of an artificial heap or bank usually of earth or stones
	(baseball) the slight elevation on which the pitcher stands
	a collection of objects laid on top of each other
	a small natural hill

molehill (verb)	mound (verb)
	form into a rounded elevation