Canticle of Canticles vs Old Testament

Canticle of Canticles and Old Testament both are nouns.

Word	Noun	Adjective	Verb	Adverb
Canticle of Canticles	Yes	No	No	No
Old Testament	Yes	No	No	No

Canticle of Canticles (noun)	Old Testament (noun)
an Old Testament book consisting of a collection of love poems traditionally attributed to Solomon but actually written much later	the collection of books comprising the sacred scripture of the Hebrews and recording their history as the chosen people; the first half of the Christian Bible