UNAUTHORIZED Synonyms: 91 Similar and Opposite Words

unauthorized

adjective

Definition of unauthorized

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 But according to the White House, the Chinese model is merely an unauthorized knock-off based on US tech. — Michael Kan, PC Magazine, 22 July 2026 In March, two pilots pulled off an unauthorized low-altitude flyover near the singer Kid Rock’s estate in Tennessee. — Brynn Tannehill, The Atlantic, 21 July 2026 Okta’s platform integrates with Clear IDV, adding an extra layer of protection to help prevent attackers from gaining unauthorized access. — Justin Zacks, CNBC, 21 July 2026 The launch last week follows a court victory for Nordisk against local compounding pharmacies making unauthorized copies. — semafor.com, 20 July 2026 See All Example Sentences for unauthorized

Recent Examples of Synonyms for unauthorized

Adjective

An improper diagnosis can trail a child through their school years, Fombonne said, but a different, underlying condition the person might have—such as depression and anxiety—might go untreated.

— Olga Khazan, The Atlantic, 20 July 2026
An independent committee investigating the cause of Hong Kong’s deadliest fire in decades heard arguments on how improper practices that evaded regulatory oversight turned a small fire into a tragedy as the case neared its conclusion Friday.

— ABC News, ABC News, 17 July 2026

Definition of improper

Adjective

Anthropic, which is valued at close to $1 trillion and has aspirations of going public in the near future, said stopping illicit distillation was a matter of national security.

— Kif Leswing,Jonathan Vanian, CNBC, 25 July 2026
Transportation Commissioner Garrett Eucalitto said improving visibility will help curtail illicit activity and will also make riders feel safer about sitting inside the shelters.

— Don Stacom, Hartford Courant, 25 July 2026

Definition of illicit

Adjective

The 15-year-old is being held on suspicion of three counts of first-degree assault and one count of second-degree unlawful possession of a firearm.

— Alicia Victoria Lozano, NBC news, 28 July 2026
California Secretary of State Shirley Weber voiced support for the bill in a statement and said the nation’s elections must remain free from intimidation and unlawful interference from any source.

— Alula Alderson, Sacbee.com, 27 July 2026

Definition of unlawful

Adjective

There has been some opposition, including from the Mauthausen Committee, Austria’s main Holocaust survivors’ group, which has argued both that a police station is inappropriate and that more should be done to draw attention to Hitler’s crimes.

— CNN Money, CNN Money, 22 July 2026
State auditors found in 2018 that $700K in voucher money being spent on cosmetics, clothing, and other inappropriate items.

— Peter Greene, Forbes.com, 22 July 2026

Definition of inappropriate

Adjective

Tell them that their behavior is embarrassing and unacceptable.

— Harriette Cole, Mercury News, 23 July 2026
Other officials told me that, in meetings of White House staff, Finer, the deputy national-security adviser, often asked what civilian death toll would be deemed unacceptable.

— David D. Kirkpatrick, New Yorker, 20 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

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Style

“Unauthorized.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unauthorized. Accessed 29 Jul. 2026.

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Synonyms of unauthorized

adjective

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