Spontaneity/ˌspɑːntəˈneɪəti/ Definition 1 of 3Pro Tip 1/3Unplanned Actions Use 'spontaneity' for actions taken without a plan, often in a fun or lively way. The party's spontaneity surprised everyone. Pro Tip 2/3Positive Surprise 'Spontaneity' often implies a surprise that leads to positive outcomes or excitement. His spontaneity added life to the dull meeting. Pro Tip 3/3Social Context Often used in social contexts to describe someone as fun-loving and unpredictable. She's appreciated for her spontaneity at social gatherings.