Vocal, a.
Etymology: [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,
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, §§ 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 Etym: [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.
1 other Webster entry under this spelling
Vocal, n.
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.
Shades of meaning
Fernald has no entry of its own for vocal; he lists it under verbal.
Where he writes about it:
Oral (L. os, the mouth) signifies uttered through the mouth or (in common phrase) by word of mouth; verbal (L. verbum, a word) signifies of, pertaining to, or connected with words, especially with words as distinguished from the ideas they convey; vocal (L. vox, the voice) signifies of or pertaining to the voice, uttered or modulated by the voice, and especially uttered with or sounding with full, resonant voice; literal (L. litera, a letter) signifies consisting of or expressed by letters, or according to the letter, in the broader sense of the exact meaning or requirement of the words used; what is called "the letter of the law" is its literal meaning without going behind what is expressed by the letters on the page. — from verbal
Vocal has primary reference to the human voice; as, vocal sounds, vocal music; vocal may be applied within certain limits to inarticulate sounds given forth by other animals than man; as, the woods were vocal with the songs of birds; oral is never so applied, but is limited to articulate utterance regarded as having a definite meaning; as, an oral statement. — from verbal