UNOFFICIAL Synonyms: 33 Similar and Opposite Words

unofficial

adjective

Definition of unofficial

as in unauthorized

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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 unofficial Oyo immediately held the unofficial title of the world’s youngest king, a mesmerizing figure even for world leaders introduced to him at national events, including South Africa’s Nelson Mandela. — Rodney Muhumuza, Los Angeles Times, 10 Sep. 2026 One family member often becomes the unofficial technology administrator and prefers everyone to use similar devices because support becomes easier. — Mark Vena, Forbes.com, 10 Sep. 2026 After months of intrigue and millions in spending, unofficial results showed Mellor winning 58% of the vote, with all precincts reporting. — Antonia Noori Farzan, The Providence Journal, 10 Sep. 2026 The more familiar and unofficial term – lie detector tests – likely fuels that perception. — Brian O'Neill, The Conversation, 10 Sep. 2026 See All Example Sentences for unofficial

Recent Examples of Synonyms for unofficial

Adjective

Ellifson said the cameras have led to a faster police response to potential critical emergencies and have been used to quickly notify law enforcement about unauthorized individuals entering school property.

— Alec Johnson, jsonline.com, 11 Sep. 2026
In Anthropic’s new cybersecurity report, the AI lab detailed an episode in which its Mythos 5 model was undergoing testing and gained unauthorized access to the internet.

— J.D. Capelouto, semafor.com, 11 Sep. 2026

Definition of unauthorized

Adjective

Language in your next lease renewal covering accent walls, hardware swaps or pre-move-out inspections, a signal that landlords are formalizing what has been an informal negotiation.

— Ryan Brennan, Charlotte Observer, 8 Sep. 2026
In a joint statement issued Tuesday, the Consultative Shipping Group (CSG) — an informal cooperation between the maritime bodies of 18 shipping nations across the globe — noted that more than 80% of global trade is transported by sea.

— Chloe Taylor, CNBC, 8 Sep. 2026

Definition of informal

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unoccupied

unofficial

unordered

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“Unofficial.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unofficial. Accessed 14 Sep. 2026.

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Synonyms of unofficial

adjective

Example Sentences

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