1. To perform or present something without preparation, notes, or prior planning; to improvise a performance
The musician decided to perform extemporaneously, creating a unique improvised set for the audience.
O músico decidiu atuar de improviso, criando um conjunto improvisado único para o público.
2. To deliver a speech, presentation, or artistic performance spontaneously without written preparation
She performed extemporaneously during the concert, surprising everyone with her spontaneous interpretation.
Ela atuou de improviso durante o concerto, surpreendendo a todos com sua interpretação espontânea.