Power chord

In music, a power chord is an interval which serves the diatonic function of a major or minor chord. It consists of two pitches or three pitches with one doubled at the octave, and thus only two pitch classes. The pitch classes are separated by a perfect fifth, or its inversion, the perfect fourth. It is sometimes notated 5, as in C5 (C power chord).

Source

• Walser, Robert (1993). Running with the Devil: Power, Gender, and Madness in Heavy Metal Music. Wesleyan University Press. ISBN 0819562602.