Definify.com

Webster 1913 Edition

(plā′gal)

Adj.

[F., from Gr.

πλάγιοσ

sidewise, slanting.]

(Mus.)

Having a scale running from the dominant to its octave; – said of certain old church modes or tunes, as opposed to those called

authentic

, which ran from the tonic to its octave.

Plagal cadence

a cadence in which the final chord on the tonic is preceded by the chord on the subdominant.

plagal ‎(comparative more plagal, superlative most plagal)

(music) Designating a mode lying a perfect fourth below the authentic form.
(music) Designating a cadence in which the subdominant chord precedes the tonic.