Definitions:

1. proceeding from natural feeling or impulse without external stimulus adjective
   • an impulsive gesture of affection
2. without forethought adjective
   • Letting the teenager borrow the car was an impulsive act that they immediately regretted.

Synonyms:

• capricious
• driving
• tearaway
• unprompted
• whimsical

NearBy Words:

• impulsively
• impulsiveness