Fifth

The fifth degree of a scale. In a diatonic scale, this is the interval between the first and fifth note of the scale. The fifth found in the major (ionian) or minor (aolian) scale is is perhaps the most popular interval among rock guitar players; playing this interval on the 5th and 6th strings (for example) results in the ubiquitous “power chord,” depending on tuning. Note that a fifth can be “perfect” (seven semitones), “diminished” (six semitones), or “augmented” (eight semitones).