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Synonyms

sudden

American  
[suhd-n] / ˈsʌd n /

adjective

  1. happening, coming, made, or done quickly, without warning, or unexpectedly.

    a sudden attack.

    Antonyms:
    gradual
  2. occurring without transition from the previous form, state, etc.; abrupt.

    a sudden turn.

    Antonyms:
    gradual
  3. impetuous; rash.

  4. Archaic. quickly made or provided.

  5. Obsolete. unpremeditated.


adverb

  1. Literary. without warning; suddenly.

noun

  1. Obsolete. an unexpected occasion or occurrence.

idioms

  1. all of a sudden, without warning; unexpectedly; suddenly. Also on a sudden

sudden British  
/ ˈsʌdən /

adjective

  1. occurring or performed quickly and without warning

  2. marked by haste; abrupt

  3. rare rash; precipitate

"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

noun

  1. archaic an abrupt occurrence or the occasion of such an occurrence (in the phrase on a sudden )

  2. without warning; unexpectedly

"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

adverb

  1. poetic without warning; suddenly

"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
sudden More Idioms  

Synonym Usage

Sudden, unexpected, abrupt describe acts, events, or conditions for which there has been no preparation or gradual approach. Sudden refers to the quickness of an occurrence, although the event may have been expected: a sudden change in the weather. Unexpected emphasizes the lack of preparedness for what occurs or appears: an unexpected crisis. Abrupt characterizes something involving a swift adjustment; the effect is often unpleasant, unfavorable, or the cause of dismay: He had an abrupt change in manner. The road came to an abrupt end.

Other Word Forms

Etymology

Origin of sudden

First recorded in 1250–1300; Middle English adjective and adverb sodain, soden, sodan(e), from Middle French soudain, from Vulgar Latin subitānus, from Latin subitāneus “going or coming stealthily,” equivalent to subitus “sudden, arising without warning” + -āneus composite adjective suffix, equivalent to -ānus + -eus; see origin at subito, -an, -eous

Explanation

Anything sudden is abrupt, quick, or unexpected. A sudden rain shower during your picnic is disappointing, while a sudden drop-off in the road ahead can be dangerous if you're on your skateboard. The stock market might take a sudden dive, panicking investors, or your favorite TV show could make a sudden change in plot, confusing you for a couple of episodes. Sudden has been used as an adjective since the 15th century, and it was once a noun, too, meaning "that which is sudden." Today the noun form is obsolete, except in the phrase "all of a sudden."

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Vocabulary lists containing sudden

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.

"Jill and I are totally heartbroken by the sudden and unexpected loss of our beloved son Alex," said the 62-year-old, who managed Wales between 1999 and 2004.

From BBC • Jun. 21, 2026

Last year, a similar campaign of drone attacks on refineries also forced fuel rationing in some Russian regions, before the refinery strikes came to a sudden halt in October.

From The Wall Street Journal • Jun. 20, 2026

The study shows that shocks can move through both horizontal and vertical pathways, as well as through direct and indirect connections, creating long chains of disruption and sudden breakdowns.

From Science Daily • Jun. 20, 2026

New Zealand had to deal with their own upheaval between Tests, following the sudden retirement of their all-time leading run-scorer Kane Williamson.

From BBC • Jun. 17, 2026

I don’t know where my sudden urge for information came from, but Dad did just call me amazing.

From "South of Somewhere" by Kalena Miller

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