The Collaborative International Dictionary of English v.0.48:

Viola \Vi"o*la\, n. [It. See Viol.] (Mus.)
   An instrument in form and use resembling the violin, but
   larger, and a fifth lower in compass.
   [1913 Webster]

   Viola da braccio [It., viol for the arm], the tenor viol,
      or viola, a fifth lower than the violin. Its part is
      written in the alto clef, hence it is sometimes called the
      alto.

   Viola da gamba [It., viol for the leg], an instrument
      resembling the viola, but larger, and held between the
      knees. It is now rarely used.

   Viola da spalla [It., viol for the shoulder], an instrument
      formerly used, resembling the viola, and intermediate in
      size between the viola and the viola da gamba.

   Viola di amore [It., viol of love: cf. F. viole d'amour], a
      viol, larger than the viola, having catgut strings upon,
      and brass or steel wires under, the keyboard. These,
      sounding sympathetically with the strings, yield a
      peculiarly soft and silvery sound. It is now seldom used.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Alto \Al"to\, n.; pl. Altos. [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.
      [1913 Webster]

   2. An alto singer.
      [1913 Webster]

   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.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

high-pitched \high-pitched\ adj.
   1. high in pitch or frequency; -- used of sounds and voices.
      Opposite of low. [Narrower terms: adenoidal, pinched,
      nasal; altissimo; alto; countertenor, alto;
      falsetto; peaky, spiky; piping; shrill, sharp;
      screaky, screechy, squeaking, squeaky, squealing;
      soprano, treble; sopranino; tenor]

   Syn: high.
        [WordNet 1.5]

   2. set at a sharp or high angle or slant; as, a high-pitched
      roof.

   Syn: steeply pitched, steep.
        [WordNet 1.5] high-power

WordNet (r) 3.0 (2006):

alto
    adj 1: of or being the lowest female voice [syn: alto,
           contralto]
    2: of or being the highest male voice; having a range above that
       of tenor [syn: countertenor, alto]
    3: (of a musical instrument) second highest member of a group;
       "alto clarinet or recorder"
    n 1: a singer whose voice lies in the alto clef
    2: the lowest female singing voice [syn: contralto, alto]
    3: the highest adult male singing voice [syn: countertenor,
       alto]
    4: (of a musical instrument) the second highest instrument in a
       family of musical instruments
    5: the pitch range of the lowest female voice

Moby Thesaurus II by Grady Ward, 1.0:

76 Moby Thesaurus words for "alto":
   Heldentenor, Meistersinger, accompaniment, aria singer, baritenor,
   baritone, bass, basso, basso buffo, basso cantante, basso continuo,
   basso ostinato, basso profundo, bassus, blues singer, canary,
   cantatrice, canto, cantor, cantus, cantus figuratus, cantus planus,
   caroler, chanter, chantress, coloratura soprano, comic bass,
   continuo, contralto, countertenor, crooner, deep bass, descant,
   diva, dramatic soprano, drone, falsetto, figured bass, ground bass,
   head register, head tone, head voice, heroic tenor, hymner,
   improvisator, lead singer, lieder singer, line, male alto,
   melodist, mezzo-soprano, opera singer, part, plain chant,
   plain song, prick song, prima donna, psalm singer,
   rock-and-roll singer, singer, singstress, songbird, songster,
   songstress, soprano, tenor, thorough bass, torch singer, treble,
   undersong, vocalist, vocalizer, voice, voice part, warbler,
   yodeler



U.S. Gazetteer Places (2000):

Alto, GA -- U.S. town in Georgia
   Population (2000):    876
   Housing Units (2000): 325
   Land area (2000):     0.825495 sq. miles (2.138023 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    0.825495 sq. miles (2.138023 sq. km)
   FIPS code:            01948
   Located within:       Georgia (GA), FIPS 13
   Location:             34.466531 N, 83.573820 W
   ZIP Codes (1990):     30510
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Alto, GA
    Alto


U.S. Gazetteer Places (2000):

Alto, TX -- U.S. town in Texas
   Population (2000):    1190
   Housing Units (2000): 534
   Land area (2000):     1.682909 sq. miles (4.358713 sq. km)
   Water area (2000):    0.000000 sq. miles (0.000000 sq. km)
   Total area (2000):    1.682909 sq. miles (4.358713 sq. km)
   FIPS code:            02188
   Located within:       Texas (TX), FIPS 48
   Location:             31.650131 N, 95.073810 W
   ZIP Codes (1990):
   Note: some ZIP codes may be omitted esp. for suburbs.
   Headwords:
    Alto, TX
    Alto