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Synonyms

unforeseen

British  
/ ˌʌnfɔːˈsiːn /

adjective

  1. not seen or known beforehand; unanticipated

"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

Something unforeseen is something that could not be predicted and was not expected. It's a surprise. If something was foreseen, you saw it coming and it wasn't a surprise. Something unforeseen is the opposite: no one saw it coming. Accidents are usually unforeseen events: no one expects to get in a car or bike accident on a given day. Winning the lottery, since it's so unlikely, would be an unforeseen event. If something was unanticipated or out of the blue, it was unforeseen. Unforeseen events can be good or bad, but they’re all surprises.

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Vocabulary lists containing unforeseen

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.

Unforeseen medical issues can put pressure on a marriage, as this couple discovered.

From MarketWatch • Oct. 27, 2025

Unforeseen road closures prevented shuttle buses from reaching the media hotel.

From BBC • Mar. 6, 2024

Unforeseen pandemics, you always got to figure some stuff out.

From Salon • Dec. 10, 2022

Unforeseen medical bills alone could create a debt problem for any potential partner who’s not top-tier wealthy.

From Slate • Jan. 13, 2022

Ah! this was that grisly Unforeseen in shape new and most monstrous.

From The Happy Warrior by Hutchinson, A. S. M. (Arthur Stuart-Menteth)