Alto (&unr_;), n.; pl. Altos (&unr_;). [It. alto high, fr. L. altus. Cf. Alt.] 1. (Mus.) Formerly the part sung by the highest male, or counter-tenor, voices; now the part sung by the lowest female, or contralto, voices, between in tenor and soprano. In instrumental music it now signifies the tenor.
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2. An alto singer.
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Alto clef (Mus.) the counter-tenor clef, or the C clef, placed so that the two strokes include the middle line of the staff. Moore.
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