Webster's Revised Unabridged Dictionary · 1913

Tetanic

Tetanic , adjective

[Compare Latin tetanicus suffering from tetanus, Greek {not transcribed}, French tétanique.]

1.
(Physiology) Of or pertaining to tetanus; having the character of tetanus; as, a tetanic state; tetanic contraction.
This condition of muscle, this fusion of a number of simple spasms into an apparently smooth, continuous effort, is known as tetanus, or tetanic contraction. — Foster
2.
(Physiology & Medicine) Producing, or tending to produce, tetanus, or tonic contraction of the muscles; as, a tetanic remedy. See Tetanic, n.

Tetanic , noun

(Physiology & Medicine) A substance (notably nux vomica, strychnine, and brucine) which, either as a remedy or a poison, acts primarily on the spinal cord, and which, when taken in comparatively large quantity, produces tetanic spasms or convulsions.