Open English Wordnet
Nouns
(n)altoa singer whose voice lies in the alto clef (n)alto(of a musical instrument) the second highest instrument in a family of musical instruments (n)altothe pitch range of the lowest female voice Adjectives
(s)countertenor, altoof or being the highest male voice; having a range above that of tenor (s)alto(of a musical instrument) second highest member of a group“alto clarinet or recorder”