# perfect fifth

> English word · Noun

## Definitions
1. An interval equal to that of between the second and third harmonics of the harmonic series. In twelve-tone equal temperament, it spans seven semitones or five degrees of the diatonic scale.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/perfect-fifth