anointing of the sick vs last rites

anointing of the sick and last rites both are nouns.

Word	Noun	Adjective	Verb	Adverb
anointing of the sick	Yes	No	No	No
last rites	Yes	No	No	No

As nouns, anointing of the sick and last rites are synonyms defined as:

anointing of the sick and last rites: a Catholic sacrament; a priest anoints a dying person with oil and prays for salvation

Other synonyms of anointing of the sick include extreme unction.

anointing of the sick (noun)	last rites (noun)
a Catholic sacrament; a priest anoints a dying person with oil and prays for salvation	rites performed in connection with a death or burial
	a Catholic sacrament; a priest anoints a dying person with oil and prays for salvation