school of thought vs ism

school of thought and ism both are nouns.

Word	Noun	Adjective	Verb	Adverb
school of thought	Yes	No	No	No
ism	Yes	No	No	No

As nouns, school of thought and ism are synonyms defined as:

school of thought and ism: a belief (or system of beliefs) accepted as authoritative by some group or school

Other synonyms of school of thought include doctrine, philosophical system, philosophy.

school of thought (noun)	ism (noun)
a belief (or system of beliefs) accepted as authoritative by some group or school	a belief (or system of beliefs) accepted as authoritative by some group or school