Auto-

CIDE DICTIONARY

Auto-,  [Gr. self.].

•  A combining form, with the meaning of self, one's self, one's own, itself, its own.  [1913 Webster]
•  a prefix with the meaning of self-moving, self-propelling; as, an autocar, an autocarriage, an autotruck, etc., an automobile car, carriage, truck, etc.  [Webster 1913 Suppl.]

OXFORD DICTIONARY

Auto-, comb. form (usu. aut- before a vowel)
1 self (autism).
2 one's own (autobiography).
3 by oneself or spontaneous (auto-suggestion).
4 by itself or automatic (automobile).

Etymology

from or after Gk auto- f. autos self