gristmill vs mill

gristmill and mill both are nouns.

Word	Noun	Adjective	Verb	Adverb
gristmill	Yes	No	No	No
mill	Yes	No	Yes	No

As nouns, mill is a hypernym of gristmill; that is, mill is a word with a broader meaning than gristmill:

Other hypernyms of gristmill include grinder, milling machinery.

gristmill (noun)	mill (noun)
a mill for grinding grain (especially the customer's own grain)	the act of grinding to a powder or dust
	machinery that processes materials by grinding or crushing
	a plant consisting of one or more buildings with facilities for manufacturing

gristmill (verb)	mill (verb)
	grind with a mill
	produce a ridge around the edge of
	roll out (metal) with a rolling machine
	move about in a confused manner