from
The Collaborative International Dictionary of English v.0.48
Tonic \Ton"ic\, n. [Cf. F. tonique, NL. tonicum.]
1. (Phon.) A tonic element or letter; a vowel or a diphthong.
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2. (Mus.) The key tone, or first tone of any scale.
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3. (Med.) A medicine that increases the strength, and gives
vigor of action to the system.
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{Tonic sol-fa} (Mus.), the name of the most popular among
letter systems of notation (at least in England), based on
key relationship, and hence called "tonic." Instead of the
five lines, clefs, signature, etc., of the usual notation,
it employs letters and the syllables do, re, mi, etc.,
variously modified, with other simple signs of duration,
of upper or lower octave, etc. See {Sol-fa}.
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