noun.
That which is self-moving, or has the power of spontaneous movement, but is not conscious.
noun.
Specifically A self-acting machine, or one which is actuated in such a manner as to carry on for some time certain movements without the aid of external impulse.
noun.
A living being acting mechanically or as a mere machine, especially without consciousness; a person or an animal whose actions are purely involuntary or mechanical.
noun.
A person who acts in a monotonous routine manner, without active intelligence, especially without being fully aware of what he is doing.