n. & adj.
--n.
1. an invigorating medicine.
2 anything serving to invigorate.
3 tonic water.
4 Mus. the first degree of a scale, forming the keynote of a piece (see KEYNOTE 3).
--adj.
1. serving as a tonic; invigorating.
2 Mus. denoting the first degree of a scale.
3 a producing tension, esp. of the muscles. b restoring normal tone to organs.
Phrases and idioms:
tonic accent an accent marked by a change of pitch within a syllable. tonic sol-fa Mus. a system of notation used esp. in teaching singing, with doh as the keynote of all major keys and lah as the keynote of all minor keys. tonic spasm continuous muscular contraction (cf. CLONUS). tonic water a carbonated mineral water containing quinine.
Derivatives:
tonically adv.
Etymology: F tonique f. Gk tonikos (as TONE)