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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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

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

So far, the most plausible driver of recent declines in overdose deaths is a change in the illicit drug supply.

— J. Travis Donahoe, STAT, 23 Oct. 2026
But how and through whom the money flowed into the Alpha account revealed that it was intended to remain secret, more akin to a covert and illicit scheme, given that it was managed in part by a senior advisor to the president of the United States.

— Matthew Cole, Vanity Fair, 22 Oct. 2026

Definition of illicit

Adjective

Runa’s incarceration – and death months after her release – is now the subject of a lawsuit brought by her mother against Hyogo Prefectural Police alleging unlawful arrest and detention.

— Hanako Montgomery, CNN Money, 24 Oct. 2026
Last month, the seizure was ruled unlawful by the California Supreme Court.

— Iris Kwok, Los Angeles Times, 24 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

Finally, the article argues that the federal lawsuit threatens state control over election administration and could fuel further claims that election results are illegitimate.

— Los Angeles Times, Los Angeles Times, 20 Oct. 2026
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

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 27 Oct. 2026.

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Synonyms of unauthorized

adjective

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