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.

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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

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adverb

1. in a spontaneous or improvised way

   he spoke impromptu

noun

1. something that is impromptu

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

Related Words

See extemporaneous.

Etymology

Origin of impromptu

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

Explanation

Some of the best kinds of parties are impromptu ones, when you decide at the last minute to get together. The adjective impromptu describes things done or said without previous thought or preparation. Impromptu is also used as an adverb: Most people are not able to speak impromptu in front of an audience. This word was borrowed from French and ultimately derives from the Latin in prōmptū ("at hand, in readiness") from in ("in") plus a form of prōmptus ("readiness"). As you can guess from the spelling, the adjective and verb prompt are related to impromptu; they are from the same Latin verb, prōmere, "to bring forth."

Example Sentences

Hull’s homage to Spirit was seen by more than 1 million people on the Points Guy’s Instagram account — and hundreds of commenters shared their own impromptu eulogies.

From MarketWatch • May 6, 2026

My husband and I burst out laughing – not at that scene, or the clerk’s impromptu theatrics, but at this injection of delight into an otherwise mundane errand.

From Salon • May 2, 2026

It’s the nature of a changing audience that is now more likely to stumble upon comedians they haven’t seen before through short social media clips, rather than an impromptu night at a comedy club.

From Los Angeles Times • Apr. 30, 2026

“The modern view,” Mr. Sidebottom writes, “is to doubt its historical accuracy. It is a scholarly orthodoxy that the salute was no more than a one-off impromptu acclamation that went very wrong.”

From The Wall Street Journal • Apr. 3, 2026

While driving through Pennsylvania he had simply happened upon a beautiful lake, pulled over, and taken an impromptu fishing vacation in perfect serenity.

From "Seabiscuit: An American Legend" by Laura Hillenbrand

Related Words

• offhand
• spontaneous
• unscripted