(music) A small keyboard instrument that consists of a series of reed pipes, which sound when one of the keys is pressed to open a valve that allows air to pass through.

A style of music where the chords are arranged within a narrow range, and the vocal styles of two or more singers either complement or are similar to each other.

(mathematics) A function of two, three or n variables which is a solution to any of Laplace's equations

(mathematics) The solutions to Laplace's equation using spherical coordinates

plural of harmonic

(physics, music) The science of musical sounds

(mathematical analysis) A study of the representation of functions or signals as the superposition of basic waves, involving the notions of harmonic functions, trigonometric series, Fourier series, Fourier transforms, almost periodic functions, and others.

In a harmful manner.

The characteristic of being harmonious.

Onomatopoeia.