plagal, a. Mus.
(ˈpleɪgəl)
[ad. med.L. plagālis (whence It. plagale, F., Ger. plagal), f. med.L. plaga the plagal mode (Du Cange), app. a back-formation from med.L. plagius, a. med.Gr. πλάγιος plagal (πλάγιος ἦχος a plagal mode), in class. Gr. ‘oblique’, f. πλάγος side. (Cf. Ger. Seitenton a plagal mode.)]
a. In Gregorian Music, Applied to those ecclesiastical modes which have their sounds comprised between the dominant and its octave, the final being near the middle of the compass. b. plagal cadence: that form of perfect cadence in which the chord of the subdominant (major or minor) immediately precedes that of the tonic. In both senses opposed to authentic.
| 1597 Morley Introd. Mus. Annot., Euery song..which in the middle hath an eight aboue the finall keye, is of an autenticall tune; if not it is a plagall. 1609 Douland Ornith. Microl. 13 Euery Song in the beginning, rising straight beyond the final Note to a Fift, is Authenticall: but that which fals straight way to a Third, or a Fourth, vnder the finall Key, is Plagall. 1796 Burney Mem. Metastasio III. 197 If you find yourself involved in the difficulties of the Plagal tones, I am not among the Authentic. 1836 Penny Cycl. VI. 99/2 There is another kind of Cadence, to which the name Plagal is given. 1875 Ouseley Harmony xiii. 154 If the piece is serious and solemn..it is usual, especially in sacred pieces, to add to it a plagal cadence. 1880 Rockstro in Grove Dict. Mus. II. 760/2 S. Gregory added to these Modes four others, directly derived from them, and hence called Plagal Modes. |