1.Having an inherent power of action or motion. "Nothing can be said to be automatic."
2.Pertaining to, or produced by, an automaton; of the nature of an automaton; self-acting or self-regulating under fixed conditions; operating with minimal human intervention; esp. applied to machinery or devices in which certain things formerly or usually done by hand are done by the machine or device itself; as, the automatic feed of a lathe; automatic gas lighting; an automatic engine or switch; an automatic mouse; an automatic transmission. The opposite of manual. Note: Narrower terms are: autoloading(prenominal), semiautomatic; automated, machine-controlled, machine-driven; self-acting, self-activating, self-moving, self-regulating; self-locking; self-winding. Also See: mechanical.
3.(Physiol.) Not voluntary; not depending on the will; mechanical; controlled by the autonomic nervous system; without conscious control; as, automatic movements or functions. The opposite of voluntary.
4.Like the unthinking functioning of a machine. "An automatic 'thank you'"