harmony vs consonance

harmony and consonance both are nouns.

Word	Noun	Adjective	Verb	Adverb
harmony	Yes	No	No	No
consonance	Yes	No	No	No

As nouns, consonance is a hyponym of harmony; that is, consonance is a word with a more specific, narrower meaning than harmony:

Other hyponyms of harmony include harmoniousness.

harmony (noun)	consonance (noun)
an agreeable sound property	the property of sounding harmonious
compatibility in opinion and action	the repetition of consonants (or consonant patterns) especially at the ends of words
agreement of opinions
the structure of music with respect to the composition and progression of chords
a harmonious state of things in general and of their properties (as of colors and sounds); congruity of parts with one another and with the whole