snappy

adjective, snap·pi·er, snap·pi·est.

1. apt to snap or bite; snappish, as a dog.
2. impatient or irritable, as a person or a reply.
3. snapping or crackling in sound, as a fire.
4. quick or sudden in action or performance.
5. Informal. crisp, smart, lively, brisk, etc.: Only snappy people get ahead in this world.