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 OpenAI’s public tracker of misalignment, or behavior that goes against instructions or safety rules, now lists 19 incidents, ranging from accessing data without permission to making unauthorized changes to business systems. — Camila Grigera Naón, Fortune, 16 Oct. 2026 The discussion on new guidelines, expected to be published around March next year, follows June’s court victory for Novo Nordisk against local compounding pharmacies making unauthorized copies. — Tiisetso Motsoeneng, semafor.com, 16 Oct. 2026 The 21 states fully running their own marketplaces generally have more robust fraud prevention programs, such as multifactor authentication, and have reported few or none of the kinds of unauthorized sign-ups plaguing the federal marketplace. — Julie Appleby, Miami Herald, 16 Oct. 2026 In a statement to Android Authority, the company has now acknowledged the unauthorized recording issue and said it has been fixed. — Jibin Joseph, PC Magazine, 16 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
  • Additionally, improper application of diagnostic criteria, and that fact that MS symptoms can resemble those of other conditions, can sometimes lead to misdiagnosis.
    — ABC News, ABC News, 20 Oct. 2026
  • He’s also accused of having improper or unclear license plates, no proof of registration and insurance, and no proof of a driver’s license.
    — Leigh Egan, FOXNews.com, 18 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
  • Parental Controls for Shared Devices Parents can restrict access to adult and inappropriate content, which helps when kids use the same phones, tablets, or laptops.
    — StackCommerce Team, PC Magazine, 19 Oct. 2026
  • Val Chmerkovskiy has been suspended from Dancing with the Stars for one week after making an inappropriate comment toward one of the judges last week.
    — Alejandra Gularte, Vulture, 17 Oct. 2026
Definition of inappropriate
Adjective
  • Detection is no substitute for prevention, not when consequences are truly unacceptable.
    — Andrew Ginter, Forbes.com, 20 Oct. 2026
  • The win won’t change what’s frankly been an unacceptable campaign for a program that was 18-1-4 just two seasons ago.
    — Ryan Kartje, Los Angeles Times, 19 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 22 Oct. 2026.

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