Compound meter
Compound meter, compound metre, or compound time (chiefly British variation), is a time signature or meter with a triple pulse within each beat (Latham 2002a).
Compound meters are written with a time signature showing the number of divisions of the beat in each measure. For example, compound duple (two beats, each divided into three) is written as a time signature with a numerator of six, such as 6/8. A time signature of 3/4 would also contain six quavers in the measure, but by convention it is understood that 3/4 refers to three crotchet beats, while 6/8 refers to two beats divided into three.
Examples of compound meter:
- 6/8 (compound duple meter) has two beats divided into three equal parts, i.e., a primary accent on the first quaver, and a subordinate accent on the fourth quaver.
- 9/8 (compound triple meter) has three beats divided into three parts, i.e., a primary accent on the first quaver, and subordinate accents on the fourth and seventh quavers.
- 12/8 (compound quadruple meter) has four beats divided into three equal parts, i.e., a primary accent on the first quaver, a secondary accent on the seventh quaver, and subordinate accents on the fourth and tenth quavers.
Although 3/4 and 6/8 are not to be confused, they use measures of the same length, so it is easy to "slip" between them just by shifting the location of the accents. This interpretational switch has been exploited, for example, by Leonard Bernstein, in the song "America" from West Side Story, as can be heard in the prominent motif 
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Some works with compound meter:
- The Irish slip jig is characterized by being in 9/8 time.
Counter-examples, not in compound meter
Compound meter divided into three parts could theoretically be transcribed into musically equivalent simple meter using triplets. Likewise, simple meter can be shown in compound through duples. In practice, however, this is rarely done because it disrupts conducting patterns when the Tempo changes. When conducting in 6/8, conductors typically provide two beats per measure. Where the tempo is slow, however, all six beats may be performed.
Compound time is associated with "lilting" and dance-like qualities. Folk dances often use compound time. Many Baroque dances are often in compound time: some gigues, the courante, and sometimes the passepied and the siciliana.