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 Kozlowski said his concerns about Flock cameras stemmed specifically from the risk that data could be shared with unauthorized parties. — Haley Parsley, Sacbee.com, 23 Sep. 2026 His point was that there is no single profile of a property that can attract an unauthorized occupant. — Kurt Knutsson, FOXNews.com, 23 Sep. 2026 His attorneys filed a motion to dismiss the emotional distress, fraud and unauthorized use of name and likeness claims. — Scottie Andrew, CNN Money, 22 Sep. 2026 Among other things, these researchers found that the agents developed their own lingo, appeared to conspire among themselves using message boards and even considered sacrificing themselves for the sake of their unauthorized mission. — Clarence Page, Chicago Tribune, 19 Sep. 2026 See All Example Sentences for unauthorized

Recent Examples of Synonyms for unauthorized

Adjective

Similarly, the spokesperson said OpenAI models used publicly available developer keys to read demographic and economic Census Bureau data, but that the company found no evidence of improper access to Census accounts.

— Ashley Capoot, CNBC, 26 Sep. 2026
On June 29, a New Haven Superior Court jury found Stokes guilty of murder, criminal attempt to commit improper sale of a firearm, conspiracy to commit improper sale of a firearm and carrying a pistol or revolver without a permit.

— Staff Report, Hartford Courant, 24 Sep. 2026

Definition of improper

Adjective

Interior Minister Kipchumba Murkomen oversaw the destruction and warned drug traffickers that authorities would step up efforts to disrupt the illicit trade.

— ABC News, ABC News, 24 Sep. 2026
Fentanyl, a synthetic opioid up to 50 times more potent than heroin, has transformed the nation's illicit drug supply over the past decade.

— James Cirrone, FOXNews.com, 24 Sep. 2026

Definition of illicit

Adjective

Legacy admissions hasn’t been declared unlawful under the tax code, and an admissions preference doesn’t prove a donation purchased admission.

— Jayson Weingarten, Fortune, 26 Sep. 2026
Owen McIntire, 20, of Parkville, faces one count of malicious destruction of property and one count of unlawful possession of an unregistered destructive device for the March 2025 incident.

— Nathan Pilling, Kansas City Star, 25 Sep. 2026

Definition of unlawful

Adjective

The restaurant industry across the country is challenging and rife with workplace abuse and inappropriate behavior that includes issues like heavy drinking, inappropriate relationships, fights between employees and wage theft.

— Katelyn Umholtz, Kansas City Star, 29 Sep. 2026
For households, the AdGuard Family Plan also includes parental controls for restricting access to inappropriate and adult content.

— StackCommerce Team, PC Magazine, 28 Sep. 2026

Definition of inappropriate

Adjective

The group Save Our Beaches San Clemente, however, says adding more rocks on the coast to protect the railroad is unacceptable.

— Los Angeles Times, Los Angeles Times, 28 Sep. 2026
Russia's demands for Ukraine to surrender its territory, among other things, are unacceptable for Kyiv.

— HANNA ARHIROVA, Arkansas Online, 25 Sep. 2026

Definition of unacceptable

Adjective

None of that is illegitimate, and none of it shows up on a data-residency dashboard.

— Dr. Aditya Vikram Kashyap, Forbes.com, 22 Sep. 2026
The researchers suspect that others were created by AI that either hallucinated or, just like the AI agents browsing their file, couldn’t distinguish between legitimate and illegitimate instructions.

— Dan Goodin, ArsTechnica, 27 Aug. 2026

Definition of illegitimate

Browse Nearby Words

unauthentic

unauthorized

unavailability

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“Unauthorized.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unauthorized. Accessed 1 Oct. 2026.

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Synonyms of unauthorized

adjective

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