slight vs ignore

slight is a noun but ignore is not a noun.

Word	Noun	Adjective	Verb	Adverb
slight	Yes	Yes	Yes	No
ignore	No	No	Yes	No

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

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

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

slight (adjective)	ignore (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)	ignore (verb)
pay no attention to, disrespect	be ignorant of or in the dark about
	give little or no attention to
	bar from attention or consideration
	refuse to acknowledge
	fail to notice