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 Over the weekend, movie-theater chain AMC Entertainment accused Robinhood of creating an unauthorized market that imitates trading in AMC shares through its overseas platform without the company’s approval. — Camila Grigera Naón, Fortune, 10 Sep. 2026 But unauthorized use of AI isn’t just impacting niche creatives in the vertical space. — Katie Kilkenny, HollywoodReporter, 10 Sep. 2026 However, alcohol consumption is generally not permitted on public streets, sidewalks and other unauthorized public spaces. — Gabby Sartori, USA Today, 10 Sep. 2026 An internal investigation initially uncovered hundreds of allegedly unauthorized searches made between January and early September, according to the Times Union. — Christina Coulter, PEOPLE, 10 Sep. 2026 See All Example Sentences for unauthorized

Recent Examples of Synonyms for unauthorized

Adjective

Common exclusions can include pre-existing conditions, improper maintenance or installation, structural problems and certain issues involving rust, corrosion or sediment buildup.

— Ryan Brennan, Miami Herald, 15 Sep. 2026
Medicare, Medicaid, the Earned Income Tax Credit and SNAP were the four government programs with the highest amount of improper payments in 2025.

— Editorial Board, Washington Post, 14 Sep. 2026

Definition of improper

Adjective

In Virginia’s Franklin County, Henry Law made the switch from illicit moonshine production to commercial sales.

— Cole Reynolds, Washington Post, 5 Sep. 2026
Johnny’s undercover mission leads to an unexpected bromance as he gets drawn into his target’s world of illicit thrills.

— Declan Gallagher, Entertainment Weekly, 3 Sep. 2026

Definition of illicit

Adjective

He is charged with official misconduct in the first degree, which is punishable by up to 12 months behind bars, if convicted, and unlawful access to a computer in the fourth degree, which carries a maximum sentence of 90 days.

— Josh Wood, Louisville Courier Journal, 3 Sep. 2026
Investigators accused him of obstruction of justice, unlawful contracting and, among other things, claiming $127,630 in expenses linked to fictitious missions and plane tickets for nearly a dozen trips.

— Jacqueline Charles, Miami Herald, 3 Sep. 2026

Definition of unlawful

Adjective

The Star spoke to 11 current and former employees who have worked for Sanders and who all detailed various types of abuse and inappropriate behavior that had allegedly taken place at their workplace.

— Katelyn Umholtz, Kansas City Star, 15 Sep. 2026
The inappropriate touching included slapping her on the buttocks and touching her hair and thighs, the report states.

— David Goodhue, Miami Herald, 14 Sep. 2026

Definition of inappropriate

Adjective

Immigrant and human-rights advocates called the situation unacceptable, particularly given the dangers facing returning Haitians, including gang killings and surging kidnappings.

— Gérard Maxineau, Miami Herald, 11 Sep. 2026
That’s an unacceptable delay for units in active combat operations.

— Nir Goldstein, Forbes.com, 10 Sep. 2026

Definition of unacceptable

Adjective

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
Internet discussions portrayed the SPLC as a politically motivated or illegitimate actor.

— Art Jipson, The Conversation, 20 Aug. 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 17 Sep. 2026.

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Synonyms of unauthorized

adjective

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