unrehearsed

/ˌʌnrɪˈhɜːrst/
adjective
  1. Not practiced or prepared in advance; spontaneous.
    • The comedian's unrehearsed jokes were the funniest of the night.
    • Her unrehearsed speech came straight from the heart.
    • They gave an unrehearsed performance that amazed the audience.
Antonyms
What does "unrehearsed" mean? | whatsthatwordmean | whatsthatwordmean