1. (adjective) cheerfully irresponsible

• carefree
• devil-may-care
• happy-go-lucky
• harum-scarum
• slaphappy

1. (adjective) free of restraints or rules

• unrestrained

2. (adjective) cheerfully irresponsible

• irresponsible

1. (adjective) cheerfully irresponsible

• carefreeness
• insouciance
• lightheartedness
• lightsomeness
• daredevil
• harum-scarum
• hothead
• lunatic
• madcap
• swashbuckler