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 Back in August, a massive leak in El Reno, Oklahoma spewed close to four million gallons of local water into the ground, forcing the city into an unofficial stand-still. — Joe Wilkins, Futurism, 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

But Massie and other lawmakers cited the potentially politically awkward vote, which would impeach Hegseth over unauthorized military actions in Iran, as the reason.

— Justin Papp, CNBC, 16 Sep. 2026
Comparing unauthorized immigration to an invasion has become increasingly common among politicians including Nigel Farage of Reform UK, and far-right groups that have been active in organizing and attending anti-immigrant protests.

— ABC News, ABC News, 16 Sep. 2026

Definition of unauthorized

Adjective

That calculation can reveal a sizable amount of informal self-insurance that never received the same planning, funding or governance as other financial obligations.

— Randy Sadler, Forbes.com, 15 Sep. 2026
Around 400 former students and leading industry professionals made the trek from Paris for a day of conferences and informal gatherings.

— Joelle Diderich, Footwear News, 14 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 20 Sep. 2026.

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Synonyms of unofficial

adjective

Example Sentences

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