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 civilian watchmen for the ship were taking an unauthorized break during this time and were not at their posts. — Frannie Comstock, Encyclopedia Britannica, 20 Aug. 2026 Those rights protect against the unauthorized commercial use of an athlete’s name, image, likeness, signature, voice, nickname and other commercially valuable traits. — Michael McCann, Sportico.com, 20 Aug. 2026 Reynoso has been arrested 20 times since 2001, with charges including harassment, unauthorized use of a motor vehicle, assault larceny, petty larceny and robbery. — Colin Mixson, New York Daily News, 20 Aug. 2026 The approach uses other AI systems to examine models’ internal reasoning and behavior for unauthorized access, data theft, or attempts to defeat safeguards. — Alex Heath, Time, 18 Aug. 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
  • According to the Office of the Inspector General, he was investigated for a string of civil rights violations, including improper searches and conduct unbecoming of an officer.
    — Jeramie Bizzle, CBS News, 24 Aug. 2026
  • Mummified remains may also pose a significant health hazard due to toxic substances used in their preservation and microbial growth due to improper storage.
    — Jennifer Ouellette, ArsTechnica, 24 Aug. 2026
Definition of improper
Adjective
  • China’s industrial overcapacity has lowered the costs of building and operating illicit enterprises.
    — Alvin Camba, Foreign Affairs, 21 Aug. 2026
  • Then again, maybe in Kawhi’s case, even illicit payments are load-managed.
    — Mike Bianchi, The Orlando Sentinel, 20 Aug. 2026
Definition of illicit
Adjective
  • Legal experts say such a move would probably be swiftly blocked by courts, as would any unlawful deployment of military troops to polls.
    — Kevin Rector, Los Angeles Times, 23 Aug. 2026
  • The suit alleges that Paramount’s unlawful termination has caused him some $4 million in economic damages.
    — Gene Maddaus, Variety, 21 Aug. 2026
Definition of unlawful
Adjective
  • During the first week of school, a Diamond Hill-Jarvis High School teacher was placed on leave over allegations of an inappropriate relationship with a student.
    — Maven Navarro, Fort Worth Star-Telegram, 25 Aug. 2026
  • The content was inappropriate and does not reflect our values.
    — Gregg Evans, New York Times, 25 Aug. 2026
Definition of inappropriate
Adjective
  • Custard said, for the public, all this adds up to unacceptable risk.
    — Yuki Noguchi, NPR, 20 Aug. 2026
  • But to build a web of accusations based on false premises and the manipulation of reality in order to attack the Biennale and a film invited to compete is a petty and unacceptable act.
    — John Bleasdale, Variety, 19 Aug. 2026
Definition of unacceptable
Adjective
  • Internet discussions portrayed the SPLC as a politically motivated or illegitimate actor.
    — Art Jipson, The Conversation, 20 Aug. 2026
  • Holding an incomplete vote, or one that feeds into any narrative of the winner being illegitimate, would be a tremendous gift to Moscow.
    — Nick Paton Walsh, CNN Money, 19 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 26 Aug. 2026.

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