adj. Mus. (of a church mode) having sounds between the dominant and its octave (cf. AUTHENTIC). plagal cadence (or close) a cadence in which the chord of the subdominant immediately precedes that of the tonic.
[ med.L plagalis f. plaga plagal mode f. L plagius f. med. Gk plagios (in anc. Gk = oblique) f. Gk plagos side ]