Of a sinusoidal wave, an integral multiple of the frequency, i.e., the fundamental, of the wave, other than the fundamental itself. Note 1: The first overtone is twice the frequency of the fundamental, and thus corresponds to the second harmonic; the second overtone is three times the frequency of the fundamental, and thus corresponds to the third harmonic, etc. Note 2: Use of the term overtone is generally confined to acoustic waves, especially in applications related to music.