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Synonyms

impromptu

American  
[im-promp-too, -tyoo] / ɪmˈprɒmp tu, -tyu /

adjective

  1. made or done without previous preparation.

    an impromptu address to the unexpected crowds.

  2. suddenly or hastily prepared, made, etc..

    an impromptu dinner.

  3. improvised; having the character of an improvisation.


adverb

  1. without preparation.

    verses written impromptu.

noun

  1. something impromptu; an impromptu speech, musical composition, performance, etc.

  2. a character piece for piano common in the 19th century and having, despite its title, a clear-cut form.

impromptu British  
/ ɪmˈprɒmptjuː /

adjective

  1. unrehearsed; spontaneous; extempore

  2. produced or done without care or planning; improvised

"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. in a spontaneous or improvised way

    he spoke impromptu

"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. something that is impromptu

  2. a short piece of instrumental music, sometimes improvisatory in character

"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

Related Words

See extemporaneous.

Etymology

Origin of impromptu

First recorded in 1660–70; from French, from Latin in promptū “in readiness”; in, prompt

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.

Mero set out to create an impromptu performance space for artists who no longer have an outlet in downtown L.A.

From Los Angeles Times • Mar. 18, 2026

Little stone circles had been laid as impromptu memorials to the men at the site where they died, a little Palestinian flag flapping above one.

From Barron's • Mar. 15, 2026

They brought their toddler with them to watch the impromptu gig.

From BBC • Mar. 12, 2026

While White House communicators cannot police his curbside impromptu comments, they can do a far better job of informing the public on all manner of issues.

From The Wall Street Journal • Mar. 11, 2026

An impromptu celebration of the victory was held immediately.

From "Animal Farm: A Fairy Story" by George Orwell