sprain

v. injure by twisting or straining the ligaments of a joint

n. injury caused by twisting or straining the ligaments of a joint

A sprain (from the French espraindre - to wring) is an injury which occurs to ligaments caused by a sudden over stretching (for the muscle injury, see strain). The ligament is usually only stretched, but if it is completely torn, a longer period of immobilization and surgical repair may be necessary. ''
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Sprain a joint injury in which some of the fibers of a supporting ligament are ruptured but the continuity of the ligament remains intact. sprain n. [more]Sprain - Community and Resources

Noun
1. a painful injury to a joint caused by a sudden wrenching of its ligaments
(hypernym) wrench, twist, pull
(derivation) twist, wrench, turn, wrick, rick
Verb
1. twist suddenly so as to sprain; "wrench one's ankle"; "The wrestler twisted his shoulder"; "the hikers sprained their ankles when they fell"; "I turned my ankle and couldn't walk for several days"
(synonym) twist, wrench, turn, wrick, rick
(hypernym) injure, wound

(v. t.)
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.
  

(n.)
The act or result of spraining; lameness caused by spraining; as, a bad sprain of the wrist.