auto

1 of 3

noun

au·​to ˈȯ-(ˌ)tō How to pronounce auto (audio)
ˈä-
plural autos
Synonyms of autonext
: automobile

auto

2 of 3

adjective

: automatic

auto-

3 of 3

combining form

variants or before a vowel aut-
1
: self : same one
autobiography
autosuggestion
2
: automatic : self-acting
autopilot

Synonyms of auto

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Noun

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Examples of auto in a Sentence

Noun the auto gave people a level of mobility that they had never known before
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
After the invention of the internal combustion engine in 1885, the auto industry had comprised skilled laborers producing a few bespoke vehicles—affordable only to an upper stratum of society. — Literary Hub, 4 Sep. 2026 But the unyielding free market advocate likely became just as well known for his opposition to Proposition 103, the landmark 1988 insurance initiative that regulated the industry following a period of skyrocketing auto premiums. — Los Angeles Times, 4 Sep. 2026
Adjective
With a large 10-round magazine, strong muzzle break, and semi-auto action, shooters can take quick follow-up shots. — Atharva Gosavi, Interesting Engineering, 17 Oct. 2025 He also is suspected of firing a gun in New Britain — again, no one was hurt — and three times fleeing police who were on a special anti-auto theft detail in Newington. — Christine Dempsey, courant.com, 11 Jan. 2022 See All Example Sentences for auto

Word History

Etymology

Noun

by shortening

Adjective

by shortening

Combining form

borrowed from Greek, combining form of autós "self, the same" (also as third person pronoun), of uncertain origin

Note: For autós R. Beekes posits as the Indo-European forerunner *h2eu̯- "again" + *to- "that" (see that entry 1); *h2eu̯- alone is the source of Greek aû "again, another time, in turn, next" (Etymological Dictionary of Greek, Brill, 2009). G. E. Dunkel, who accepts Indo-European *a as a vowel and does not believe that all words must begin with a consonant, subsumes the first element of autós under *au̯- "away, off" (*au̯-tó- would hence originally have been a deictic, "the one over there") and subsumes Greek aû under *h2u-, by-form of *h2o- "with it, at it, and, also" (Lexikon der indogermanischen Partikeln und Pronominalstämme, Heidelberg, 2014). Older etymological proposals (as a link between au- in autós and Sanskrit ásuḥ "life") are summarized by E. Schwyzer in Griechische Grammatik (Munich, 1990 [1938]), pp. 613-14.

First Known Use

Noun

1899, in the meaning defined above

Adjective

1876, in the meaning defined above

Time Traveler
The first known use of auto was in 1876

Phrases Containing auto

Rhymes for auto

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Browse Nearby Words

autistic savant
auto
auto-
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Cite this Entry

“Auto.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/auto. Accessed 7 Sep. 2026.

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Kids Definition

auto

1 of 2 noun
au·​to
ˈȯt-ō, 
ˈät-
plural autos
: automobile

auto-

2 of 2
see aut-

More from Merriam-Webster on auto

Britannica.com: Encyclopedia article about auto

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