Sprain \Sprain\ (spr[=a]n), v. t. [imp. & p. p. {Sprained}
(spr[=a]nd); p. pr. & vb. n. {Spraining}.] [OF. espreindreto
press, to force out, F. ['e]preindre, fr. L. exprimere. See
{Express}, v. t., and cf. {Spraints}.]
To weaken, as a joint, ligament, or muscle, by sudden and
excessive exertion, as by wrenching; to overstrain, or
stretch injuriously, but without luxation; as, to sprain
one's ankle.
[1913 Webster]