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
Origin: < Gr autos, self
See auto in American Heritage Dictionary 4
noun pl. au·tos
Origin: Short for automobile.
Origin: , from autos, self.
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