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 In June 2020, amid protests following George Floyd's death, NBC installed a temporary protective wall as a precautionary move, but there were no reported incidents of unauthorized access or damage. — Taijuan Moorman, USA Today, 16 July 2026 She and the school’s treasurer were fired in 2013 after being indicted on 26 felony counts of theft in office, unauthorized use of property, tampering with evidence and tampering with records. — Jennifer Smith Richards, ProPublica, 16 July 2026 The ban has pushed many fans in Saudi Arabia toward unauthorized streaming sites and VPNs. — Matthew Martin, semafor.com, 15 July 2026 California Highway Patrol arrested Kevin Michael Silva on July 6 on suspicion of DUI and operating an unauthorized law enforcement patrol vehicle, according to a Facebook post by CHP Stockton. — Velvet Wu july 14, Sacbee.com, 14 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

In the latter case, it is found especially in countries where alcoholic drinks are hard to afford or illicit.

— ABC News, ABC News, 17 July 2026
In Phoenix, this shift in the illicit drug supply has combined with heat, meth and homelessness to create an emerging crisis of overdose deaths in America’s fifth-largest city.

— Josh Katz, New York Times, 15 July 2026

Definition of illicit

Adjective

Since the tournament began, police have declared unlawful assemblies twice, including late July 5, when a crowd began throwing bottles at officers.

— Ryan Macasero, Mercury News, 19 July 2026
Opponents counter that California already bars unlawful firearm manufacturing with 3-D printers, and that ghost gun recoveries have declined since the state adopted a series of new laws and enforcement efforts.

— Los Angeles Times, Los Angeles Times, 19 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

Critics say such plans are wholly unacceptable because light pollution from so many large, bright satellites would radically degrade views of the night sky.

— Mary Randolph, Scientific American, 16 July 2026
For the union, this is unacceptable and yet another issue their members are facing.

— Carmela Karcher, CBS News, 14 July 2026

Definition of unacceptable

Adjective

Signature-matching efforts sometimes disqualify more legitimate than illegitimate ballots.

— Jeremy Kohler, ProPublica, 15 July 2026
If the Hand of God effectively flipped the bird to the English side—then as now, Diego Maradona’s first goal was farcically illegitimate—the Argentine captain’s subsequent score was something out of the divine intervention catalogue.

— Anthony Crupi, Sportico.com, 14 July 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 23 Jul. 2026.

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Synonyms of unauthorized

adjective

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