Spontaneous combustion (as in spontaneous human combustion) can also mean the alleged phenomenon of a human being (and, one assumes, other animals) suddenly, unexpectedly bursting into flames, in dramatic cases reducing the person's torso to a pile of ashes, often leaving behind charred limbs. Spontaneous human combustion--never actually witnessed--is actually at present a theory to explain the many cases that have been found where the torso of a person, often female, often overweight, has been reduced to ashes, without any obvious external cause. There is, of course, considerable disagreement as to what the source of such deaths might be--often it is denied that any genuine "spontaneous human combustion" ever occurs.
See Anomalous Phenomena and combustion.
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