(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.

(music) a type of minor scale with the 3rd and 6th notes lowered by one semitone, with the interval pattern:

plural of harmonic minor scale

(music) a note that is played or sung between two chords that is not a part of either chord

plural of non-harmonic tone

plural of second-harmonic generation

a nonlinear optical process in which two photons with the same frequency interact with a nonlinear material

(mathematics, physics) oscillating motion (as of a pendulum) in which the acceleration of the oscillator has an equal magnitude but opposite direction to the displacement of it from the equilibrium position

(harmonic analysis, representation theory, topology) A branch of harmonic analysis dealing with generalised Fourier transforms that act on functions defined on Hausdorff locally compact topological groups.

plural of simple harmonic motion