heap vs charcoal pile

heap and charcoal pile both are nouns.

Word	Noun	Adjective	Verb	Adverb
heap	Yes	No	Yes	No
charcoal pile	Yes	No	No	No

As nouns, charcoal pile is a hyponym of heap; that is, charcoal pile is a word with a more specific, narrower meaning than heap:

heap: a collection of objects laid on top of each other
charcoal pile: a pile of wooden billets, covered with turf or moistened clay, used to produce wood charcoal.

heap (noun)	charcoal pile (noun)
a car that is old and unreliable	a pile of wooden billets, covered with turf or moistened clay, used to produce wood charcoal.
a collection of objects laid on top of each other
(often followed by `of') a large number or amount or extent