Source : Webster's Revised Unabridged Dictionary (1913)

Tetany \Tet"a*ny\, n. (Med.)
   A morbid condition resembling tetanus, but distinguished from
   it by being less severe and having intermittent spasms.

Source : WordNet®

tetany
     n : clinical neurological syndrome characterized by muscular
         twitching and cramps and (when severe) seizures;
         associated with calcium deficiency (hypoparathyroidism)
         or vitamin D deficiency or alkalosis [syn: {tetanilla}, {intermittent
         tetanus}, {intermittent cramp}, {apyretic tetanus}]