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 The 2-1 decision rejected Anthropic's argument that the Department of Defense's ban on its Claude models was arbitrary, unauthorized and unconstitutional. — Lora Kolodny, CNBC, 13 Oct. 2026 Cybersecurity protects systems against unauthorized access and manipulation, while functional safety protects people, equipment and the environment when systems fail or behave incorrectly. — Gregory Shahnovsky, Forbes.com, 13 Oct. 2026 In all, some 700 agents found a way to communicate, using an unauthorized message board, and coordinate an attack on the computer systems of fellow AI company Hugging Face. — Laurent Belsie, Christian Science Monitor, 13 Oct. 2026 Microsoft tells CyberGuy that two unauthorized posts appeared during the period when its account was compromised. — Kurt Knutsson, FOXNews.com, 11 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
  • In 2024, its football program acknowledged impermissible recruiting contacts during the COVID-19 recruiting dead period, improper tryouts and unauthorized coaching by noncoaching staff.
    — Jackson Thompson OutKick, FOXNews.com, 11 Oct. 2026
  • The production was shut down in Livingston, Montana last Saturday when locals complained about the production’s impact on the Livingston food bank and improper warnings about hazardous stunts.
    — Pat Saperstein, Variety, 10 Oct. 2026
Definition of improper
Adjective
  • From December 2024 to May 2025, the international law enforcement body Interpol conducted Operation Pangea XVII, in which authorities in 90 countries seized more than 50 million doses of illicit pharmaceuticals.
    — Andrew Yockey, Fortune, 15 Oct. 2026
  • Participants were also asked about their alcohol consumption, smoking and illicit drug use.
    — New Atlas, New Atlas, 14 Oct. 2026
Definition of illicit
Adjective
  • The complaint seeks a declaration that DeWine’s executive order is unlawful.
    — Michael McCann, Sportico.com, 16 Oct. 2026
  • Paporakis faces one felony count of making a terrorist threat and one felony count of unlawful possession of a weapon.
    — Landon Mion, FOXNews.com, 16 Oct. 2026
Definition of unlawful
Adjective
  • On the police's Facebook account on Tuesday, officers criticized inappropriate comments and warned that sharing or joking about such incidents can worsen the impact on any victim.
    — ABC News, ABC News, 13 Oct. 2026
  • In addition, pharmaceutical advertising or education aimed at doctors may also increase inappropriate prescribing, probably increases the number of prescriptions written, and may increase the costs of prescriptions.
    — Ed Silverman, STAT, 9 Oct. 2026
Definition of inappropriate
Adjective
  • The idea of not spending evenings with my kid is, kids are, is completely unacceptable.
    — Michael Birnbaum The Washington Post, Arkansas Online, 14 Oct. 2026
  • OpenAI took months to discover the incident and notify the Australian agencies affected — that’s unacceptable by my standard.
    — Rumman Chowdhury, Vogue, 13 Oct. 2026
Definition of unacceptable
Adjective
  • An adult child can claim authority over the meaning of a life without proving that everything inherited is therefore illegitimate.
    — Literary Hub, Literary Hub, 9 Oct. 2026
  • Saman admitted to purchasing much of his inventory from brokers or middlemen, which the department identified as illegitimate distributors of the brands.
    — Glenn Taylor, Footwear News, 8 Oct. 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 20 Oct. 2026.

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