Canticles vs Song of Songs

Canticles and Song of Songs both are nouns.

Word	Noun	Adjective	Verb	Adverb
Canticles	Yes	No	No	No
Song of Songs	Yes	No	No	No

As nouns, Canticles and Song of Songs are synonyms defined as:

Canticles and Song of Songs: an Old Testament book consisting of a collection of love poems traditionally attributed to Solomon but actually written much later

Other synonyms of Canticles include Canticle of Canticles, Song of Solomon.

Canticles (noun)	Song of Songs (noun)
an Old Testament book consisting of a collection of love poems traditionally attributed to Solomon but actually written much later	an Old Testament book consisting of a collection of love poems traditionally attributed to Solomon but actually written much later