spontaneous

/spɒntˈe‍ɪni‍əs/

/spɑnˈteɪniəs/

spontaneous

done or happening naturally, without any prior thought or planning

antonyms : induced

a person who tends to act on impulse or in the moment, without much planning or considering the consequences or potential risks of their actions

synonyms : ad-lib

Examples

1. Yesterday, Debby did as she pleased and took a spontaneous trip to the beach, enjoying the freedom of making decisions on her own.

2. Number five, be spontaneous.

3. Usually these mutations are spontaneous.

4. Kevin's skating is really spontaneous.