1. spoke or performed without preparation; improvised
Usage: past tense of extemporize

Examples

• The speaker extemporized when his notes were lost.
• She extemporized a brilliant response to the unexpected question.
• The jazz musician extemporized a solo that captivated the audience.
• When the teleprompter failed, the news anchor extemporized the rest of the broadcast.
• The teacher extemporized a lesson when the projector broke down.
• He extemporized his wedding speech after forgetting his written remarks.