[im-promp-too, -tyoo]
made or done without previous preparation: an impromptu address to the unexpected crowds.
suddenly or hastily prepared, made, etc.: an impromptu dinner.
improvised; having the character of an improvisation.
without preparation: verses written impromptu.
something impromptu; an impromptu speech, musical composition, performance, etc.
a character piece for piano common in the 19th century and having, despite its title, a clear-cut form.

1660–70; < French < Latin in promptū in readiness; see in, prompt

1. See extemporaneous. Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To impromptu
World English Dictionary
impromptu (ɪmˈprɒmptjuː)
1.  unrehearsed; spontaneous; extempore
2.  produced or done without care or planning; improvised
3.  in a spontaneous or improvised way: he spoke impromptu
4.  something that is impromptu
5.  a short piece of instrumental music, sometimes improvisatory in character
[C17: from French, from Latin in promptū in readiness, from promptus (adj) ready, prompt]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Word Origin & History

1669 (adv.), 1764 (adj.), from Fr. impromptu (1659), from L. in promptu "in readiness," from in "in" + promptu, abl. of promptus "readiness," from pp. of promere "to bring out," from pro- "before, forward, for" + emere "to obtain" (see exempt).
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
Encyclopedia Britannica


a 19th-century piano composition intended to produce the illusion of spontaneous improvisation. In keeping with this fundamental premise, there is no particular form associated with the impromptu, although ternary and rondo schemes are common. The style of the music is similar to that of other compositions of the period, with such designations as fantasie, caprice, and bagatelle.

Learn more about impromptu with a free trial on

Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source
Example sentences
With the turn of a crank, slowly a big iron door slid back, allowing the chimps
  access to their impromptu photo studio.
Shelly had discovered it one night when the band she belonged to then had
  played at an impromptu concert there.
His detention, by all visible measures, was not impromptu.
Impromptu picking camps spring up and disband in a matter of weeks, leaving
  garbage pits and barren land in their wake.
Copyright © 2014, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature