nociceptor

noun

1. A sensory receptor that sends signals that cause the perception of pain in response to a potentially damaging stimulus.

   “He divides receptors into three classes— "nociceptors", such as the nerve-endings for pain and hunger, "beneceptors", such as the nerve-endings stimulated when sugar melts on the tongue, and "neutroceptors", such as the nerve-endings in the eye and ear, called " neutroceptors" because they receive more or less indiscriminately both pleasant and unpleasant messages.”

   “The “beneceptors,” “nociceptors,” and "neutroceptors” generally signalled stimuli that were, respectively, beneficial, harmful, or neutral as regards the organism or its species.”