duple
\ DOO-puhl, DYOO- \, adjective;
1.having two parts; double; twofold.
2.Music . having two or sometimes a multiple of two beats in a measure: duple meter .
Quotes:
About the same number of poems set to duple or mixed meter tunes have the most characteristic poetic meter of six-syllable lines.
-- Timothy J. Cooley, "Making Music in the Polish Tatras," 2005
The tune is in duple time, as are most corridors with a basic line longer than eight syllables.
-- Américo Paredes, "A Texas-Mexican Cancionero: Folksongs of the Lower Border," 1976
Origin:
Duple entered English in the mid-1500s. It comes from the Latin word duplus which meant "double."
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