aortic aneurysm vs aneurism

aortic aneurysm and aneurism both are nouns.

Word	Noun	Adjective	Verb	Adverb
aortic aneurysm	Yes	No	No	No
aneurism	Yes	No	No	No

As nouns, aneurism is a hypernym of aortic aneurysm; that is, aneurism is a word with a broader meaning than aortic aneurysm:

aortic aneurysm: an aneurysm of the aorta
aneurism: a cardiovascular disease characterized by a saclike widening of an artery resulting from weakening of the artery wall

Other hypernyms of aortic aneurysm include aneurysm.

aortic aneurysm (noun)	aneurism (noun)
an aneurysm of the aorta	a cardiovascular disease characterized by a saclike widening of an artery resulting from weakening of the artery wall