arson vs incendiarism

arson and incendiarism both are nouns.

Word	Noun	Adjective	Verb	Adverb
arson	Yes	No	No	No
incendiarism	Yes	No	No	No

As nouns, arson and incendiarism are synonyms defined as:

Other synonyms of arson include fire-raising.

arson (noun)	incendiarism (noun)
malicious burning to destroy property	malicious burning to destroy property