[a. F. trio (a. 1600 in Hatz.-Darm., according to whom) a. It. trio, f. tre three, ‘formed in imitation of duo.’]
1. Mus. A composition for three voices or instruments; also, a company of three performers singing or playing such a composition.
1724. Short Explic. For. Wds. in Mus. Bks., Tria, or Trio, Musick in Three Parts is so called, either for Voices or Instruments, or both together.
1727–41. Chambers, Cycl., Trio, in music; a part of a concert wherein three persons sing; or more properly a musical composition consisting of three parts.
1775. Mme. D’Arblay, Early Diary (1889), II. 134. It seemed to be a sort of trio between an old woman, a young woman, and a young man.
1824. Byron, Juan, XVI. xlv. Oh! the long evenings of duets and trios!
1885. ‘Mrs. Alexander,’ At Bay, iii. Mademoiselle Antoinette and Elsie, assisted by the singing-master, were performing a trio.
b. Name for a second or subordinate division of a minuet or other dance movement, or of a scherzo or march; commonly in a different key and style from the main division, which is repeated after it.
Supposed to be so called because originally written for three instruments or in three parts.
1840. Encycl. Brit. (ed. 7), XXI. 387/1. The term trio is also applied to a movement in 3/4th time, which often follows the minuet in a piece of instrumental music.
1889. F. Corder, in Grove, Dict. Mus., IV. 172/2. How the second minuet acquired the name of Trio is not quite clear. Bach only calls it so in the few instances in which it is written in three parts—as opposed to the minuet in two. Ibid., 173/1. By the time of Haydn the term Trio is firmly established, and even in his earliest works … there are two minuets, each with a trio.
2. A group or set of three: a. of persons.
[1763. Mrs. Brooke, Lady J. Mandeville (1820), 55. Foreseeing we should be a very awkward party to-day à trio, I sent … to ask three or four very agreeable girls … to come and ramble all day with us in the woods.]
1789. H. Walpole, Lett. to Mrs. H. More, 22 April. The lady flowers and their lovers enter in pairs or trios.
1836. W. Irving, Astoria, xliv. III. 38. The trio of Kentucky hunters, Robinson, Rezner, and Hoback.
1904. Verney Mem., II. 59. Chatting with this trio of charming cousins.
b. of things or animals; in quot. 1777 a stanza of three lines; in Cricket, three runs.
1777. trans. Chesterfield’s Lett., I. xxxv. Misc. Wks. II. 110. I will tell you very frankly, I could as soon get off fifty thousand of his trios as fifty.
1856. Kane, Arct. Expl., II. xiii. 132. [Walrus] surging in loving trios from crack to crack.
1873. Earle, Philol. Eng. Tongue (ed. 2), § 109. The general adoption of this trio of vowel-sounds as the basis of phonology.
1882. Daily Tel., 24 June. At 237 Studd resumed in place of Ramsay, but was almost at once driven by Giffen for a trio.
c. Cards. At piquet, a combination of three aces, kings, queens, or knaves in one hand.
1891. in Cent. Dict.
