unrest vs upheaval

unrest and upheaval both are nouns.

Word	Noun	Adjective	Verb	Adverb
unrest	Yes	No	No	No
upheaval	Yes	No	No	No

As nouns, upheaval is a hypernym of unrest; that is, upheaval is a word with a broader meaning than unrest:

unrest: a state of agitation or turbulent change or development
upheaval: a state of violent disturbance and disorder (as in politics or social conditions generally)

Other hypernyms of unrest include Sturm und Drang, turbulence.

unrest (noun)	upheaval (noun)
a feeling of restless agitation	disturbance usually in protest
a state of agitation or turbulent change or development	(geology) a rise of land to a higher elevation (as in the process of mountain building)
	a state of violent disturbance and disorder (as in politics or social conditions generally)
	a violent disturbance