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 Anthropic has said that its Claude models broke out of what was supposed to be an isolated testing environment and gained unauthorized access to the systems of three real organizations. — Beatrice Nolan, Fortune, 31 July 2026 In 2026, a surge of legal disputes arose from the unauthorized use of individuals' images, voices, and creative works. — Schuyler Moore, Forbes.com, 30 July 2026 The conduct resulted in approximately $54,000 in unauthorized government charges, prosecutors said. — Anthony Thompson, USA Today, 30 July 2026 Elliott ran an unauthorized query of a North Carolina license plate registration, according to an SBI press release. — Noah Vinsky, Charlotte Observer, 29 July 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
  • Critics of Medicaid expansion argued that increasing the number of people who could get health insurance through the program would increase fraud and improper enrollment.
    — Ben Zdencanovic, The Conversation, 3 Aug. 2026
  • The conservative Paragon Health Institute’s president, Brian Blase, wrote in a recent webpost that the HHS report’s conclusion on the scope of improper enrollment is likely an undercount.
    — Julie Appleby, Miami Herald, 3 Aug. 2026
Definition of improper
Adjective
  • Meanwhile, 18-to-25-year-olds saw declines in the use of nicotine products, tobacco, cigarette, alcohol and binge drinking in the past month as well as the use of illicit drugs and prescription stimulants or opioids within the past year.
    — Mary Kekatos, ABC News, 1 Aug. 2026
  • But the illicit art is only part of the operatic tale of the literal rise and metaphorical fall of what have become informally known as the graffiti towers.
    — Los Angeles Times, Los Angeles Times, 31 July 2026
Definition of illicit
Adjective
  • Since Congress never approved that relocation, the move is unlawful, the lawsuit alleges.
    — Chiara Eisner, NPR, 3 Aug. 2026
  • When the Miami commission approved the unlawful ordinance last summer, the change went into effect immediately.
    — Tess Riski July 31, Miami Herald, 31 July 2026
Definition of unlawful
Adjective
  • The siblings-in-law addressed comments from Alli McBee suggesting their relationship had been inappropriate.
    — Deirdre Durkan, PEOPLE, 4 Aug. 2026
  • Students also need to learn when AI use is inappropriate, when a primary source has to be read directly and when a judgment is too consequential to delegate.
    — Ray Ravaglia, Forbes.com, 4 Aug. 2026
Definition of inappropriate
Adjective
  • The episode has added to a growing chorus of concern among AI safety advocates, who argue that agents capable of independently identifying and exploiting unknown vulnerabilities across multiple companies’ infrastructure present an unacceptable risk.
    — Beatrice Nolan, Fortune, 29 July 2026
  • Conditional approval remains a possibility for firms demonstrating no unacceptable risks.
    — John Koetsier, Forbes.com, 29 July 2026
Definition of unacceptable
Adjective
  • But that’s forcing them to wrestle with the idea that any action taken by a party is illegitimate, anti-democratic rigging — something the other team can use to depress the base.
    — David Weigel, semafor.com, 22 July 2026
  • Signature-matching efforts sometimes disqualify more legitimate than illegitimate ballots.
    — Jeremy Kohler, ProPublica, 15 July 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 5 Aug. 2026.

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More from Merriam-Webster on unauthorized

Nglish: Translation of unauthorized for Spanish Speakers

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