unauthorized

adjective

Definition of unauthorizednext
as in improper
without permission; not authorized an unauthorized use of government vehicles Unauthorized personnel are not allowed in the building.

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Example Sentences

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.
Recent Examples of unauthorized Legal risks mount for OpenAI OpenAI faces mounting legal risks stemming from cyber incidents linked to its AI models, after the firm alerted more than 100 organizations to unauthorized activities. — Eleanor Mueller, semafor.com, 5 Oct. 2026 The case involved a popular Japanese anime voice actor who demanded that TikTok close an account over its unauthorized use of an AI clone of his trademark baritone. — ABC News, 5 Oct. 2026 OpenAI reported that the agents used unauthorized communication channels, exploited vulnerabilities and engaged in reward hacking. — Babajide Ojuola, Forbes.com, 5 Oct. 2026 These sports businesses have alleged that counterfeit and unauthorized goods are sold through Temu, AliExpress, and similar online marketplaces. — Michael McCann, Sportico.com, 5 Oct. 2026 See All Example Sentences for unauthorized
Recent Examples of Synonyms for unauthorized
  1. improper
  2. illicit
  3. unlawful
  4. inappropriate
  5. unacceptable
  6. illegitimate
Adjective
  • Electrical issues — like faulty wiring, overloaded power strips, and improper extension cord usage — are the leading cause of fatal fires so far this year.
    — Lillian Bonsignore, New York Daily News, 4 Oct. 2026
  • The action comes as Livingston locals raised concerns about the film’s impact on local business — and notably the city’s sole food bank — as well as improper notification about hazardous stunts.
    — Payton Turkeltaub, Variety, 4 Oct. 2026
Definition of improper
Adjective
  • The Financial Action Task Force, the global money-laundering watchdog, has warned that criminals exploit citizenship and residency programs to conceal their identities, launder illicit wealth and evade justice.
    — Arkansas Online, Arkansas Online, 3 Oct. 2026
  • Those illicit techniques include attaching a GPS tracker to a car or using cell-tower data to track a potential offender.
    — Rafael A. Mangual, Washington Post, 2 Oct. 2026
Definition of illicit
Adjective
  • In a blow to the investment migration industry, the European Union's top court ruled Malta's golden passport program unlawful in April 2025, declaring that EU citizenship could not be sold.
    — Arkansas Online, Arkansas Online, 3 Oct. 2026
  • In a blow to the investment migration industry, the European Union’s top court ruled Malta’s golden passport program unlawful in April 2025, declaring that EU citizenship could not be sold.
    — Isabel Debre, Los Angeles Times, 2 Oct. 2026
Definition of unlawful
Adjective
  • The Portland Trail Blazers fired new play-by-play television broadcaster Braiden Bell on Thursday when past inappropriate social media posts resurfaced just hours after the team announced his hiring.
    — ABC News, ABC News, 2 Oct. 2026
  • Sheriff’s officials said, investigators as of Thursday had not uncovered evidence indicating Chen had inappropriate physical contact with a child.
    — Rosalio Ahumada, Sacbee.com, 2 Oct. 2026
Definition of inappropriate
Adjective
  • With a team that has a margin of error as small as the Dolphins, these penalties are unacceptable.
    — Miami Herald, Miami Herald, 5 Oct. 2026
  • Likewise, the underlying crisis of commercially unacceptable risk in the Strait isn’t anywhere close to being resolved.
    — David Faris, Washington Post, 5 Oct. 2026
Definition of unacceptable
Adjective
  • None of that is illegitimate, and none of it shows up on a data-residency dashboard.
    — Dr. Aditya Vikram Kashyap, Forbes.com, 22 Sep. 2026
  • The researchers suspect that others were created by AI that either hallucinated or, just like the AI agents browsing their file, couldn’t distinguish between legitimate and illegitimate instructions.
    — Dan Goodin, ArsTechnica, 27 Aug. 2026
Definition of illegitimate

Browse Nearby Words

unauthentic
unauthorized
unavailability
See all Nearby Words

Cite this Entry

“Unauthorized.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unauthorized. Accessed 9 Oct. 2026.

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