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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

  • unexplainable adjective

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.

Beijing hasn’t declared any exercises in the area, sparking a new aviation mystery following an unexplained pause in military flights around Taiwan.

From The Wall Street Journal • Apr. 5, 2026

Navy pilots seeing unexplained aerial phenomenon, then by a 2023 Congressional subcommittee hearing on the topic.

From Los Angeles Times • Mar. 13, 2026

These vignettes are where Gyllenhaal’s directorial eye shines the brightest, and where “The Bride!” brims with promise — just before the first of the film’s several unexplained narrative shifts.

From Salon • Mar. 8, 2026

He was pronounced dead at the scene and his death is currently being treated as "unexplained", the force said.

From BBC • Feb. 23, 2026

Dr. McNally testified that Mrs. Colbey’s pregnancy was at high risk for "unexplained fetal death" because of her age and lack of prenatal care.

From "Just Mercy" by Bryan Stevenson