dissertation vs treatise

dissertation and treatise both are nouns.

Word	Noun	Adjective	Verb	Adverb
dissertation	Yes	No	No	No
treatise	Yes	No	No	No

As nouns, treatise is a hypernym of dissertation; that is, treatise is a word with a broader meaning than dissertation:

dissertation: a treatise advancing a new point of view resulting from research; usually a requirement for an advanced academic degree
treatise: a formal exposition

dissertation (noun)	treatise (noun)
a treatise advancing a new point of view resulting from research; usually a requirement for an advanced academic degree	a formal exposition