Part of speech:

Adjective: "She gave an extemporaneous talk;" "The speeches were all extemporaneous."

Other forms: 

The noun for the quality is "extemporaneity," as in "The speech was very well-rehearsed; no one would mistake it for extemporaneity" or "She's well-known for her extemporaneity."

And the noun for the person is "extemporizer," as in "He and his parents are excellent extemporizers, but please don't ever ask me to give a toast."

The adverb is "extemporaneously."

And the verb is "extemporize." It's usually intransitive and means "to speak on the fly," as in "He extemporized at dinner" and "She sat at the piano and extemporized."  But it can also be transitive and mean "to create something on the fly," as in "The cast extemporizes entire songs on Whose Line Is It Anyway."

When you want a more formal, more serious-sounding adjective than "improvised," "on-the-spot," or "on-the-fly," pick "extemporaneous."

You might talk about extemporaneous talks, speeches, songs, and performances.

To use the verb, talk about people extemporizing, often on or about some topic: "We asked our tour guide about local customs, and he was happy to extemporize on them." Or, say that someone extemporizes a story, a song, an explanation, or a description: "He extemporized a brief history of local customs."

examples:

"He sings, dances and does extemporaneous impersonations of everyone from the Russian ballet mistress from his school to the British director on 'Baby Driver,' Edgar Wright." 
— Jacob Bernstein, New York Times, 1 July 2017

"All parents who make a habit of telling bedtime stories to their kids know that on occasion a tale composed by accident has enough nice features to make it seem worth keeping. The greatest of these improvised-and-then-impaled-on-a-card stories is, of course, 'Alice in Wonderland,' extemporized on a golden afternoon and recalled at leisure later."
— Adam Gopnik, New York Times, 8 November 2017

has this page helped you understand "extemporaneous"?

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Thanks for letting me know!
If you have any questions about this word, please message me at Liesl@HiloTutor.com.

study it:

Explain the meaning of "extemporaneous" without saying "off-the-cuff" or "spur-of-the-moment."

try it out:

In an episode of Firefly, when a crowd chants excitedly for Jayne to give a speech, he gives it his best shot. He's not the greatest extemporizer ever: 

"Uh... I'm no good with words. Don't... don't use 'em much, myself... But I want to thank you all for being here, and for thinking so much of me... Far as I see it, you people been given the shortest end of the stick ever been offered a human soul in this crap-hill 'verse... But you TOOK that end... well, you TOOK it. And that's... well, I guess that's somethin.'"

The crowd cheers. So I guess he extemporized okay.

Extemporaneous speeches can be awkward, like Jayne's, as well as heartful and genuine, or anything in between.

How do you feel about your own ability to extemporize? Can you address a crowd and move them with an extemporaneous speech, without sounding awkward? If so, what are your secrets: how do you do it? 

If you like, use this space to write. (To save your work, copy and paste it into an email or a document.)

before you review, play:

Try to spend 20 seconds or more on the game below. Don’t skip straight to the review—first, let your working memory empty out.

This month, our game is "Smorgasbord of Wordly Lore!"

Try a trivia question each day. It’ll have something to do with a food or a drink. You can play on hard mode by answering the question cold, or play on easy mode by highlighting the multiple choice options. To see the correct answer, scroll all the way down. Enjoy!

Try this one today: The Persian phrase "sir o sakar," meaning "milk and sugar," gave us what name for a cloth or pattern?

Highlight below to reveal the multiple choice options.…
A. chiffon
B. cashmere
C. seersucker

review this word:

1. The opposite of EXTEMPORANEOUS is

A. REHEARSED.
B. HEARTFELT.
C. ORGANIZED.

2. As the Futurama gang watches an opera, then joins in on a song, Dr. Zoidberg is shocked at the extemporaneity, singing "_____"

A. I watch TV with that guy!
B. The music's bad and you should feel bad!
C. I can't believe everybody's just ad-libbing!

Answers to the review questions: 1. A 2. C Answer to the game question: Seersucker. It has alternating bands of smooth (milky) and bumpy (sugary) cloth.

a final word:

I hope you're enjoying Make Your Point. It's made with love. I'm Liesl Johnson, a reading and writing tutor on a mission to explore, illuminate, and celebrate words. From my blog: On vocabulary...       36 ways to study words.       Why we forget words, & how to remember them.       How to use sophisticated words without being awkward. On writing...       How to improve any sentence.       How to motivate our kids to write.       How to stop procrastinating and start writing.       How to bulk up your writing when you have to meet a word count. From my heart: a profound thanks to the generous patrons, donors, and sponsors that make it possible for me to write these emails. If you'd like to be a patron or a donor, please click here. If you'd like to be a sponsor and include your ad in an issue, please contact me at Liesl@HiloTutor.com. A disclaimer: When I write definitions, I use plain language and stick to the words' common, useful applications. If you're interested in authoritative and multiple definitions of words, I encourage you to check a dictionary. Also, because I'm American, I stick to American English when I share words' meanings, usage, and pronunciations; these elements sometimes vary across world Englishes.