Viola tricolor vs viola

Viola tricolor and viola both are nouns.

Word	Noun	Adjective	Verb	Adverb
Viola tricolor	Yes	No	No	No
viola	Yes	No	No	No

As nouns, viola is a hypernym of Viola tricolor; that is, viola is a word with a broader meaning than Viola tricolor:

Viola tricolor: a common and long cultivated European herb from which most common garden pansies are derived
viola: any of the numerous plants of the genus Viola

Viola tricolor (noun)	viola (noun)
a common and long cultivated European herb from which most common garden pansies are derived	any of the numerous plants of the genus Viola
	a bowed stringed instrument slightly larger than a violin, tuned a fifth lower