What is "plagal cadence"

Plagal \Pla"gal\ (pl[=a]"gal), a. [F., from Gr. pla`gios 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.

n. (context music English) A falling cadence in which a subdominant chord precedes the tonic; especially used in an ending Amen.

n. a cadence (frequently ending church music) in which the chord of the subdominant precedes the chord of the tonic [syn: amen cadence]