The strict and formal definitions of autonomic and autonomous are as follows:[2]
AUTONOMIC
SYLLABICATION: au·to·nom·ic
ADJECTIVE: 1. Physiology a. Of, relating to, or controlled by the autonomic nervous system. b. Occurring involuntarily; automatic: an autonomic reflex. 2. Resulting from internal stimuli; spontaneous.
OTHER FORMS: auto·nomi·cal·ly ADVERB
ATONOMOUS
SYLLABICATION: au·ton·o·mous
ADJECTIVE: 1. Not controlled by others or by outside forces; independent: an autonomous judiciary; an autonomous division of a corporate conglomerate. 2. Independent in mind or judgment; self-directed. 3a. Independent of the laws of another state or government; self-governing. b. Of or relating to a self-governing entity: an autonomous legislature. c. Self-governing with respect to local or internal affairs: an autonomous region of a country. 4. Autonomic.
ETYMOLOGY: From Greek autonomos: auto-, auto- + nomos, law; OTHER FORMS: au·tono·mous·ly ADVERB