The musical term alto, meaning "high" in Italian (Latin: altus), refers to the second highest part of a contrapuntal musical texture and is also applied to its associated vocal range, especially in choral music. More rarely it describes the highest male solo voice type (usually designated countertenor), and it is also the root word of contralto, the lowest standard female voice type. When designating instruments, "alto" likewise can refer either to the corresponding vocal range (alto flute & alto trombone, respectively the lowest and highest common instruments of their families) or to musical role (treble or alto recorder and alto clarinet, with ranges of F4-F6 and G2-B♭5).

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