tetanus

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun An acute, often fatal disease characterized by spasmodic contraction of voluntary muscles, especially those of the neck and jaw, and caused by the toxin of the bacillus Clostridium tetani, which typically infects the body through a deep wound.
• noun Physiology A state of continuous muscular contraction, especially when induced artificially by rapidly repeated stimuli.

from The Century Dictionary.

• noun A disease characterized by a more or less violent and rigid spasm of many or all of the muscles of voluntary motion. ; ; ;
• noun In physiology, the state or condition of prolonged contraction which a muscle assumes under rapidly repeated stimuli.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Med.) A painful and usually fatal disease, resulting generally from a wound, and having as its principal symptom persistent spasm of the voluntary muscles. When the muscles of the lower jaw are affected, it is called locked-jaw, or lickjaw, and it takes various names from the various incurvations of the body resulting from the spasm.
• noun (Physiol.) That condition of a muscle in which it is in a state of continued vibratory contraction, as when stimulated by a series of induction shocks.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun pathology, countable A serious and often fatal disease caused by the infection of an open wound with the anaerobic bacterium Clostridium tetani, found in soil and the intestines and faeces of animals.
• noun physiology, countable A state of muscle tension caused by sustained contraction arising from a rapid series of nerve impulses which do not allow the muscle to relax.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a sustained muscular contraction resulting from a rapid series of nerve impulses
• noun an acute and serious infection of the central nervous system caused by bacterial infection of open wounds; spasms of the jaw and laryngeal muscles may occur during the late stages