Spasm \Spasm\, n. [F. spasme, L. spasmus, Gr. ?, from ?, ?, to draw, to cause convulsion. Cf. Span, v. t.]

1. (Med.) An involuntary and unnatural contraction of one or more muscles or muscular fibers.

Note: Spasm are usually either clonic or tonic. In clonic spasm, the muscles or muscular fibers contract and relax alternately in very quick succession. In tonic spasm, the contraction is steady and uniform, and continues for a comparatively long time, as in tetanus.

2. A sudden, violent, and temporary effort or emotion; as, a spasm of repentance.

Cynic spasm (Med.) See under Cynic.

Spasm of the chest. See Angina pectoris, under Angina.

Source: Webster's Revised Unabridged Dictionary (1913)