Pronunciation: (sim"pu-thet'ik),[key] —adj. 1. characterized by, proceeding from, exhibiting, or feeling sympathy; sympathizing; compassionate: a sympathetic listener. 2. acting or affected by, of the nature of, or pertaining to a special affinity or mutual relationship; congenial: With their many similar tastes, he found her a most sympathetic companion. 3. looking upon with favor (often fol. by to or toward): She is sympathetic to the project. 4. Anat.,Physiol. a. pertaining to that part of the autonomic nervous system consisting of nerves that arise from the thoracic and lumbar regions of the spinal cord, and functioning in opposition to the parasympathetic system, as in stimulating heartbeat, dilating the pupil of the eye, etc.
b. Obs.pertaining to the autonomic nervous system in its entirety.
5. Physics.noting or pertaining to vibrations, sounds, etc., produced by a body as the direct result of similar vibrations in a different body.