Alto is a musical term, derived from the Latin word altus, meaning "high”. For musical instruments, "alto" frequently refers to a member of an instrument family that has the second highest range, below that of the soprano, as in the term "alto saxophone". The current saxophone family includes the soprano, alto, tenor and baritone saxes, but instruments higher than soprano and lower than baritone have been made.
In choral music, "alto" describes the second highest voice part in a four-part chorus. The alto range in choral music is approximately from G3 (the G below middle C) to F5 (the F in the second octave above middle C). Alto is often used to describe the voice type that typically sings this part, the other three standard modern choral voice classifications are soprano, tenor and bass. (adapted from Wikipedia)
