名詞 alto:

1. a singer whose voice lies in the alto clef
2. the lowest female singing voice
   同義詞：contralto
3. the highest adult male singing voice
   同義詞：countertenor
4. (of a musical instrument) the second highest instrument in a family of musical instruments
5. the pitch range of the lowest female voice

形容詞 alto:

1. of or being the lowest female voice
   同義詞：contralto
2. of or being the highest male voice; having a range above that of tenor
   同義詞：countertenor
3. (of a musical instrument) second highest member of a group