brush down vs jaw

brush down is not a noun while jaw is a noun.

Word	Noun	Adjective	Verb	Adverb
brush down	No	No	Yes	No
jaw	Yes	No	Yes	No

As verbs, jaw is a hypernym of brush down; that is, jaw is a word with a broader meaning than brush down:

brush down (noun)	jaw (noun)
	holding device consisting of one or both of the opposing parts of a tool that close to hold an object
	the part of the skull of a vertebrate that frames the mouth and holds the teeth
	the bones of the skull that frame the mouth and serve to open it; the bones that hold the teeth

brush down (verb)	jaw (verb)
reprimand	talk socially without exchanging too much information
	censure severely or angrily
	talk incessantly and tiresomely
	chew (food); to bite and grind with the teeth