• Pseudo-octave

    Origin

    - + octave

    Full definition of pseudo-octave

    Noun

    pseudo-octave

    (plural pseudo-octaves)
    1. (music) An interval whose frequency ratio is not 2:1 (that of the octave), but is perceived or treated as equivalent to this ratio, and whose pitches are considered equivalent to each other as with octave equivalency.
    © Wiktionary