harmonization vs harmony

harmonization and harmony both are nouns.

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

As nouns, harmony is a hypernym of harmonization; that is, harmony is a word with a broader meaning than harmonization:

harmonization: a piece of harmonized music
harmony: the structure of music with respect to the composition and progression of chords

Other hypernyms of harmonization include musical harmony.

harmonization (noun)	harmony (noun)
singing in harmony	an agreeable sound property
a piece of harmonized music	compatibility in opinion and action
	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