Meaning of the word extemporaneous in English

What does extemporaneous mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

extemporaneous

US /ekˌstem.pəˈreɪ.ni.əs/
UK /ekˌstem.pəˈreɪ.ni.əs/

Adjective

spoken or done without preparation

Example:
He gave an extemporaneous speech at the conference.
Her performance was completely extemporaneous, yet flawless.