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Synonyms

unexplained

British  
/ ˌʌnɪkˈspleɪnd /

adjective

  1. not explained or understood

    unexplained phenomena

"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

Other Word Forms

Explanation

Something that's unexplained isn't known or made clear, like an unexplained creaking sound coming from the attic of your grandparents' creepy house. Anything without a clear reason for happening or existing is unexplained, whether it's the mysterious crack in the kitchen window or some lines of movie dialogue spoken in a language you don't understand (and without subtitles). When you explain something, you describe what it is, how it works, or why it exists — and then it's explained. Add the prefix un-, meaning "not," and you get unexplained.

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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.

Unexplained absences can be an early sign of political trouble in China, though officials are known to have missed engagements for innocuous reasons such as illness.

From The Wall Street Journal • Feb. 15, 2026

The cause was undetermined—Sudden Unexplained Death in Childhood, or SUDC, they called it.

From Slate • May 13, 2024

The star of Unexplained: Caught on Camera paid £200 for the doll from the St Columba's Hospice shop and now plans to keep it at her home in Cheshire.

From BBC • Mar. 12, 2024

Unexplained rapid weight loss in older people could be a sign of underlying disease and can be linked with increased risk of falls and fractures, as well as a poorer long-term prognosis.

From Science Daily • Feb. 1, 2024

The lobby of the Department of the Unexplained is pitch-black.

From "Amari and the Night Brothers" by B.B. Alston