alter ego

noun

al·​ter ego ˌȯl-tər-ˈē-(ˌ)gō How to pronounce alter ego (audio)
also
-ˈe-(ˌ)gō How to pronounce alter ego (audio)
plural alter egos
Synonyms of alter ego
1
: a second self or different version of oneself: such as
a
: a trusted friend
b
: the opposite side of a personality
Clark Kent and his alter ego Superman
c
: counterpart sense 3
a fictional character that is the author's alter ego
2
law : a person or entity vicariously liable for another (such as an agent)
… because the Cuban bank had not physically participated in the expropriation, it could not be considered an alter ego of the Government in the context of the Citibank case.—The New York Times

Did you know?

In Latin, alter ego literally means "second I". An alter ego can be thought of as a person's clone or second self. A professional alter ego might be a trusted aide who knows exactly what the boss wants done. A personal alter ego might be a close friend who is almost like a twin. Alter ego can also refer to the second, hidden side of one's own self. In Robert Louis Stevenson's classic The Strange Case of Doctor Jekyll and Mr. Hyde, Dr. Jekyll is a good-hearted, honorable man; but after taking a potion, his alter ego, the loathsome and diabolical Mr. Hyde, takes over his personality.

Synonyms of alter ego

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Examples of alter ego in a Sentence

a trusted adviser who is the President's alter ego over the years the state's other senator became his alter ego as well as his political ally
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.
Does Absolutely feel like an alter ego or an extension of yourself? — Christina Perrier, InStyle, 30 July 2026 Peter Parker’s alter ego lands in Australia, India and Saudi Arabia on Thursday, with Japan going on Friday. — Anthony D'alessandro, Deadline, 28 July 2026 Born six weeks after Vernon and a kind of public-facing alter ego for the singer at past Eaux Claires, Francis has materialized as a surprise guest at the Dijon set. — Steven Zeitchik, HollywoodReporter, 28 July 2026 Nicholas Galitzine stars as Prince Adam – and his buff alter ego He-Man – who returns to his homeland of Eternia to reunite with old friends and battle evil, over-the-top Skeletor (Jared Leto). — Brian Truitt, USA Today, 24 July 2026 See All Example Sentences for alter ego

Word History

Etymology

borrowed from Latin alter egō "close friend," literally "other I," perhaps as translation of Greek állos egṓ, héteros egṓ

Note: Cf. M. Tullius cicero, Letters to Atticus 3.15.4.: "… me enim ipsum multo magis accuso, deinde te quasi me alterum et simul meae culpae socium quaero." ("I am reproaching myself far more than you, and if I do reproach you it is as my alter ego; also I am looking for someone to share the blame" - translation by D. R. Shackleton Bailey.)

First Known Use

1537, in the meaning defined at sense 1

Time Traveler
The first known use of alter ego was in 1537

Rhymes for alter ego

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Browse Nearby Words

altered chord
alter ego
alterer
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Cite this Entry

“Alter ego.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/alter%20ego. Accessed 6 Aug. 2026.

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Kids Definition

alter ego

noun
al·​ter ego ˌȯl-tər-ˈē-gō How to pronounce alter ego (audio)
1
: a trusted friend or personal representative
2
: the opposite side of a personality

Legal Definition

alter ego

noun
al·​ter ego ˈȯl-tər-ˈē-gō How to pronounce alter ego (audio)
: second self
especially : a person or entity vicariously liable for another (as an agent)
had the officer been the alter ego of the corporation —J. J. White and R. S. Summers
compare instrumentality

Note: The concept of a legal alter ego is used primarily to hold the controlling parties of a corporation personally liable instead of limiting liability to the corporate entity.

Etymology

Latin, literally, second I

More from Merriam-Webster on alter ego

Nglish: Translation of alter ego for Spanish Speakers

Britannica.com: Encyclopedia article about alter ego

Last Updated: - Updated example sentences
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