presentism vs ism

presentism and ism both are nouns.

Word	Noun	Adjective	Verb	Adverb
presentism	Yes	No	No	No
ism	Yes	No	No	No

As nouns, ism is a hypernym of presentism; that is, ism is a word with a broader meaning than presentism:

presentism: the doctrine that the Scripture prophecies of the Apocalypse (as in the Book of Revelations) are presently in the course of being fulfilled
ism: a belief (or system of beliefs) accepted as authoritative by some group or school

Other hypernyms of presentism include doctrine, philosophical system, philosophy, school of thought.

presentism (noun)	ism (noun)
the doctrine that the Scripture prophecies of the Apocalypse (as in the Book of Revelations) are presently in the course of being fulfilled	a belief (or system of beliefs) accepted as authoritative by some group or school