disagreement vs dissent

disagreement and dissent both are nouns.

Word	Noun	Adjective	Verb	Adverb
disagreement	Yes	No	No	No
dissent	Yes	No	Yes	No

As nouns, dissent is a hyponym of disagreement; that is, dissent is a word with a more specific, narrower meaning than disagreement:

disagreement (noun)	dissent (noun)
a difference between conflicting facts or claims or opinions	the act of protesting; a public (often organized) manifestation of dissent
the speech act of disagreeing or arguing or disputing	(law) the difference of one judge's opinion from that of the majority
a conflict of people's opinions or actions or characters	a difference of opinion

disagreement (verb)	dissent (verb)
	withhold assent
	be of different opinions
	express opposition through action or words