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 In 2026 evaluations, a testing misconfiguration left models connected to the internet, and four models gained unauthorized access to real third-party systems. — David Goldman, CNN Money, 26 Oct. 2026 In addition, Monroe said that Target has safeguards preventing unauthorized agents and bots from accessing customer accounts and initiating transactions on a human’s behalf. — Mia Sato, The Verge, 22 Oct. 2026 Fortunately, transparency logs account for much of that failure, but this measure requires parties to actively monitor massive feeds and works only after unauthorized certificates have been issued. — Dan Goodin, ArsTechnica, 20 Oct. 2026 Police said groups numbering from several hundred to more than 1,000 people formed unauthorized marches across central Paris on Saturday. — ABC News, 18 Oct. 2026 See All Example Sentences for unauthorized

Recent Examples of Synonyms for unauthorized

Adjective

The department disagrees that the monitors did anything improper, Pels said.

— STEVE PEOPLES, Arkansas Online, 27 Oct. 2026
Immigration lawyers say a nearly 10-month improper detention would be rare but not unprecedented.

— Ryan J. Foley, The Orlando Sentinel, 27 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

Her colleagues voted twice last year to censure her for inappropriate criticism of city employees.

— Alene Tchekmedyian, Los Angeles Times, 23 Oct. 2026
Specifically, Pickard said his understanding of the immunity deal is that his testimony about adultery and an inappropriate relationship cannot be used against him as part of the Uniform Code of Military Justice.

— Matt Schooley, CBS News, 22 Oct. 2026

Definition of inappropriate

Adjective

These efforts should be lauded because lawyering solely to please Trump without an iota of reasonableness according to prescribed rules of law to which all lawyers must adhered is simply unacceptable.

— Miles J. Zaremski, The Orlando Sentinel, 27 Oct. 2026
But critics, like the Civic Federation, are denouncing the budget plan, calling it an unacceptable abdication of responsibility to meet the fiscal realities facing the city.

— Adam Harrington, CBS News, 22 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 29 Oct. 2026.

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Synonyms of unauthorized

adjective

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