What is another word for

spontaneous

spontaneous as in happening or arising without apparent external cause
  • "spontaneous laughter"
  • "spontaneous combustion"
  • "a spontaneous abortion"

Synonyms

  • self-generatedhappening or arising without apparent external cause; originating from the self
spontaneous as in said or done without having been planned or written in advance
  • "he made a few ad-lib remarks"

Synonyms

  • ad-libremark made spontaneously without prior preparation; perform without preparation; with little or no preparation or forethought; said or done without having been planned or written in advance
  • unwrittenbased on custom rather than documentation; using speech rather than writing; said or done without having been planned or written in advance