I do pay for the M-W.com unabridged, so I might as well let it flex.

Main Entry: har·mo·ny Pronunciation Guide

Pronunciation: primarystresshärmschwanemacron, primarystresshadotm-, -ni

Function: noun

Inflected Form(s): -es

Etymology: Middle English armonye, from Middle French armonie, from Old French, from Latin harmonia, from Greek, joint, concord, harmony, from harmos joint, fastening -- more at ARM

1 a archaic : tuneful sound : MELODY b : musicality of language

2 a : the combination of simultaneous musical notes into a chord (as a triad) b : the structure of a piece of music according to the composition and progression of its chords -- compare MELODY, RHYTHM c : the science of the structure, relation, and progression of chords in homophonic composition

3 : combination into a consistent whole : INTEGRATION

4 a : CORRESPONDENCE, AGREEMENT, ACCORD b : internal calm : TRANQUILLITY

5 : a systematic arrangement of parallel literary passages (as of the Gospels) for the purpose of showing agreement or harmony

6 : HARMONIC SUTURE

7 : the arrangement of parts in pleasing relation to each other ; specifically : the orderly combination of colors resulting in an aesthetically pleasing general effect -- compare COLOR BALANCE

But what is happiness except the simple harmony between a man and the life he leads?

Albert Camus

I studied harmony and composition in a very spontaneous manner.

Alejo Carpentier

The hidden harmony is better than the obvious.

Pablo Picasso

Harmony makes small things grow, lack of it makes great things decay.

Sallust

Like everything metaphysical the harmony between thought and reality is to be found in the grammar of the language.

Ludwig Wittgenstein

All creatures must learn to coexist. That's why the brown bear and the field mouse can share their lives in harmony. Or course, they can't mate or the mice would explode.

Betty White

Music is a lady that I still love because she gives me the air that I breathe. We need all sorts of nourishment. And music satisfies and nourishes the hunger within ourselves for connection and harmony.

Cat Stevens