adjective

extemporaneous

ik-stem-puh-RAY-nee-us/ɪkˌstempəˈreɪniəs/

Spoken or done with little or no preparation.

She gives an extemporaneous toast when the host invites her to speak.

An interrupted diner immediately gives an impromptu address: a compact two-moment sequence makes the unexpected invitation and immediate speaking visibly connected.

Etymology

exLatinout of

+temporLatintime, moment

+aneousLatinadjective-forming ending

The Latin expression literally meant “out of time,” but conveyed acting according to the needs of the moment. Something done or furnished “at the time” thus came to mean unpremeditated, including speech or performance with little preparation.

In context

Valeria Lipovetsky62:15

another type of communication that people often like to develop in is how to answer extemporaneous questions so if you are speaking at an event and you are getting spontaneous questions

Handling Women's Most Awkward Moments with Modern Etiquette

More examples

His extemporaneous remarks sound more natural than his prepared speech.
The musicians delight the crowd with an extemporaneous performance.
Even her extemporaneous answers are clear and thoughtful.

Forms

extemporaneous

extemporaneously adverb — With little or no advance preparation.

extemporize verb — To speak or perform without advance preparation.

Similar words

impromptu: Emphasizes being arranged or undertaken on the spur of the moment.
improvised: Emphasizes creating something as needed with available resources.
spontaneous: Emphasizes a natural impulse rather than deliberate planning.