hardening of the arteries vs arterial sclerosis

hardening of the arteries and arterial sclerosis both are nouns.

Word	Noun	Adjective	Verb	Adverb
hardening of the arteries	Yes	No	No	No
arterial sclerosis	Yes	No	No	No

As nouns, hardening of the arteries and arterial sclerosis are synonyms defined as:

hardening of the arteries and arterial sclerosis: sclerosis of the arterial walls

Other synonyms of hardening of the arteries include arteriosclerosis, coronary-artery disease, induration of the arteries.

hardening of the arteries (noun)	arterial sclerosis (noun)
sclerosis of the arterial walls	sclerosis of the arterial walls