upheaval vs convulsion

upheaval and convulsion both are nouns.

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

As nouns, upheaval and convulsion are synonyms defined as:

Other synonyms of upheaval include turmoil.

upheaval (noun)	convulsion (noun)
disturbance usually in protest	a physical disturbance such as an earthquake or upheaval
(geology) a rise of land to a higher elevation (as in the process of mountain building)	violent uncontrollable contractions of muscles
a state of violent disturbance and disorder (as in politics or social conditions generally)	a sudden uncontrollable attack
a violent disturbance	a violent disturbance