Source : Webster's Revised Unabridged Dictionary (1913)

Vocal \Vo"cal\, a. [L. vocalis, fr. vox, vocis, voice: cf. F.
   vocal. See {Voice}, and cf. {Vowel}.]
   1. Of or pertaining to the voice or speech; having voice;
      endowed with utterance; full of voice, or voices.

            To hill or valley, fountain, or fresh shade, Made
            vocal by my song.                     --Milton.

   2. Uttered or modulated by the voice; oral; as, vocal melody;
      vocal prayer. ``Vocal worship.'' --Milton.

   3. Of or pertaining to a vowel or voice sound; also, ?poken
      with tone, intonation, and resonance; sonant; sonorous; --
      said of certain articulate sounds.

   4. (Phon.)
      (a) Consisting of, or characterized by, voice, or tone
          produced in the larynx, which may be modified, either
          by resonance, as in the case of the vowels, or by
          obstructive action, as in certain consonants, such as
          v, l, etc., or by both, as in the nasals m, n, ng;
          sonant; intonated; voiced. See {Voice}, and {Vowel},
          also Guide to Pronunciation, [sect][sect] 199-202.
      (b) Of or pertaining to a vowel; having the character of a
          vowel; vowel.

   {Vocal cords} or {chords}. (Anat.) See {Larynx}, and the Note
      under {Voice}, n., 1.

   {Vocal fremitus} [L. fremitus a dull roaring or murmuring]
      (Med.), the perceptible vibration of the chest wall,
      produced by the transmission of the sonorous vibrations
      during the act of using the voice.

   {Vocal music}, music made by the voice, in distinction from
      {instrumental music}; hence, music or tunes set to words,
      to be performed by the human voice.

   {Vocal tube} (Anat.), the part of the air passages above the
      inferior ligaments of the larynx, including the passages
      through the nose and mouth.

Vocal \Vo"cal\, n. [Cf. F. vocal, LL. vocalis.]
   1. (Phon.) A vocal sound; specifically, a purely vocal
      element of speech, unmodified except by resonance; a vowel
      or a diphthong; a tonic element; a tonic; -- distinguished
      from a subvocal, and a nonvocal.

   2. (R. C. Ch.) A man who has a right to vote in certain
      elections.

Source : WordNet®

vocal
     adj 1: relating to or designed for or using the singing voice;
            "vocal technique"; "the vocal repertoire"; "organized
            a vocal group to sing his compositions" [ant: {instrumental}]
     2: having or using the power to produce speech or sound; "vocal
        organs"; "all vocal beings hymned their praise"
     3: using the voice in song; "vocal music" [syn: {sung}]
     4: given to expressing yourself freely or insistently;
        "outspoken in their opposition to segregation"; "a vocal
        assembly" [syn: {outspoken}]
     5: using the voice in speech; "vocal communication"; "either
        silent or vocal prayers"; "vocal noises" [syn: {spoken}]
     6: full of the sound of voices; "a playground vocal with the
        shouts and laughter of children"