autonomic (adj.)

Middle English -ik, -ick, word-forming element making adjectives, "having to do with, having the nature of, being, made of, caused by, similar to," from French -ique and directly from Latin -icus or from cognate Greek -ikos "in the manner of; pertaining to." From PIE adjective suffix *-(i)ko, which also yielded Slavic -isku, adjectival suffix indicating origin, the source of the -sky (Russian -skii) in many surnames. In chemistry, indicating a higher valence than names in -ous (first in benzoic, 1791).

In Middle English and after often spelled -ick, -ike, -ique. Variant forms in -ick (critick, ethick) were common in early Modern English and survived in English dictionaries into early 19c. This spelling was supported by Johnson but opposed by Webster, who prevailed.

1777, "subject to its own laws" (in translations of Montesquieu); 1780, "pertaining to autonomy;"  from Greek autonomos "having one's own laws," of animals, "feeding or ranging at will," from autos "self" (see auto-) + nomos "law" (from PIE root *nem- "assign, allot; take"). Compare privilege. Used mostly in metaphysics and politics; see autonomic. Related: Autonomously.