midden vs heap

midden and heap both are nouns.

Word	Noun	Adjective	Verb	Adverb
midden	Yes	No	No	No
heap	Yes	No	Yes	No

As nouns, heap is a hypernym of midden; that is, heap is a word with a broader meaning than midden:

Other hypernyms of midden include agglomerate, cumulation, cumulus, mound, pile.

midden (noun)	heap (noun)
a heap of dung or refuse	a car that is old and unreliable
(archeology) a mound of domestic refuse containing shells and animal bones marking the site of a prehistoric settlement	a collection of objects laid on top of each other
	(often followed by `of') a large number or amount or extent