The definition of auto is an abbreviation for automobile which is a machine with an engine, four wheels, and room for passengers that is used to transport people on land.
(noun)A car is an example of an auto.
See auto in Webster's New World College Dictionary
adjective, noun
Origin: < Gr autos, self
See auto in American Heritage Dictionary 4
noun pl. au·tos
Origin:
Origin: Short for automobile
.or aut-
prefixOrigin:
Origin: Greek
Origin: , from autos, self
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