ipsedixitism vs assertion

ipsedixitism and assertion both are nouns.

Word	Noun	Adjective	Verb	Adverb
ipsedixitism	Yes	No	No	No
assertion	Yes	No	No	No

As nouns, assertion is a hypernym of ipsedixitism; that is, assertion is a word with a broader meaning than ipsedixitism:

ipsedixitism: an unsupported dogmatic assertion
assertion: a declaration that is made emphatically (as if no supporting evidence were necessary)

Other hypernyms of ipsedixitism include asseveration, averment.

ipsedixitism (noun)	assertion (noun)
an unsupported dogmatic assertion	a declaration that is made emphatically (as if no supporting evidence were necessary)
	the act of affirming or asserting or stating something