A violent attack of shivering, often associated with a fever. Rigor may also refer to stiffness or rigidity of body tissues, as in rigor mortis.
Shivering. If prolonged, it is generally accompanied by fever, and may be a sign of the onset of some acute disease such as INFLUENZA, PNEUMONIA, or some internal in?ammation. Rigor mortis is the name given to the sti?ness that ensues soon after death. (See DEATH, SIGNS OF; MUSCLE.)
n. 1. an abrupt attack of shivering and a sensation of coldness, accompanied by a rapid rise in body temperature. This often marks the onset of a fever and may be followed by a feeling of heat, with copious sweating. 2. see rigor mortis.
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