Auto- \Au"to-\ An abbrev. of automobile, used as a prefix with the meaning of self-moving, self-propelling; as, an autocar, an autocarriage, an autotruck, etc., an automobile car, carriage, truck, etc. Auto- \Au"to-\ [Gr. ? self.] A combining form, with the meaning of self, one's self, one's own, itself, its own.