improvisational
definition
characterized by the spontaneous creation or performance of something without preparation
example
During the festival, the actors engaged in improvisational theater, creating scenes on the spot based on audience suggestions.
synonyms
spontaneousunpreparedimpromptu
word origin — From the Latin 'improvisus', meaning 'unforeseen', combining 'in-' (not) and 'providere' (to foresee or provide).