viol vs viola d'amore

viol and viola d'amore both are nouns.

Word	Noun	Adjective	Verb	Adverb
viol	Yes	No	No	No
viola d'amore	Yes	No	No	No

As nouns, viola d'amore is a hyponym of viol; that is, viola d'amore is a word with a more specific, narrower meaning than viol:

viol: any of a family of bowed stringed instruments that preceded the violin family
viola d'amore: viol that is the tenor of the viol family

Other hyponyms of viol include viola da braccio, bass viol, gamba, viola da gamba.

viol (noun)	viola d'amore (noun)
any of a family of bowed stringed instruments that preceded the violin family	viol that is the tenor of the viol family