diptych vs fine art

diptych and fine art both are nouns.

Word	Noun	Adjective	Verb	Adverb
diptych	Yes	No	No	No
fine art	Yes	No	No	No

As nouns, fine art is a hypernym of diptych; that is, fine art is a word with a broader meaning than diptych:

diptych: a painting or carving (especially an altarpiece) on two panels (usually hinged like a book)
fine art: the products of human creativity; works of art collectively

Other hypernyms of diptych include art.

diptych (noun)	fine art (noun)
a painting or carving (especially an altarpiece) on two panels (usually hinged like a book)	the products of human creativity; works of art collectively