slight vs brush off

slight is a noun but brush off is not a noun.

Word	Noun	Adjective	Verb	Adverb
slight	Yes	Yes	Yes	No
brush off	No	No	Yes	No

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

Other hypernyms of slight include brush aside, discount, dismiss, disregard, ignore, push aside.

slight (noun)	brush off (noun)
a deliberate discourteous act (usually as an expression of anger or disapproval)

slight (adjective)	brush off (adjective)
(quantifier used with mass nouns) small in quantity or degree; not much or almost none or (with `a') at least some
lacking substance or significance
being of delicate or slender build

slight (verb)	brush off (verb)
pay no attention to, disrespect	bar from attention or consideration