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Synonyms

undeclared

British  
/ ˌʌndɪˈklɛəd /

adjective

  1. not announced or acknowledged publicly

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Explanation

Anything undeclared isn't stated or admitted to in a public way. An undeclared political candidate may be seriously considering running for President, but she hasn't officially announced it. An undeclared war is conflict and violence that affects people's lives despite the fact that no government is officially calling it a war. If you're a college student with an undeclared major, you haven't decided which subject to focus on. Once you choose, you'll have a declared major. When it comes to paying taxes, any income that someone hides from the IRS is also undeclared: "She had to pay a fine because of those undeclared tips."

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

On Saturday Iran also struck the town of Dimona in Israel's Negev desert, an area linked to Israel's undeclared nuclear programme.

From BBC • Mar. 23, 2026

The six American service members who died in this undeclared war were “heroes,” Leavitt said.

From Salon • Mar. 6, 2026

Acai bowls were recalled over possible plastic contamination, while sesame miso salad and hot honey mustard dressing were recalled over undeclared allergens.

From Los Angeles Times • Feb. 25, 2026

Mr. Hoppy is a retired mechanic who lives in an apartment directly above the widowed Mrs. Silver, the object of his undeclared crush.

From The Wall Street Journal • Feb. 23, 2026

It’s ironic how Ms. G is helping us write about an undeclared war, and that night she was helping us fight it.

From "The Freedom Writers Diary" by The Freedom Writers