harum-scarum

Adjective

• cheerfully irresponsible
  • carefree with his money
    
  • freewheeling urban youths
    
  • had a harum-scarum youth
    

Adverb

• in a wild or reckless manner
  • dashing harum-scarum all over the place
    
  • running pell-mell up the stairs
    

Noun

• a reckless impetuous irresponsible person

Related words

• Synonyms: 
  carefree , devil-may-care , freewheeling , happy-go-lucky , slaphappy , pell-mell , daredevil , madcap , hothead , swashbuckler , lunatic