careless

 
Pronunciation: /ˈkɛːlɪs/

adjective

  • not giving sufficient attention or thought to avoiding harm or errors: she had been careless and had left the window unlocked a careless error
  • (of an action or its result) showing or caused by a lack of attention: he admitted careless driving a careless error
  • (careless of/about) not concerned or worried about: he was careless of his own safety
  • showing no interest or effort; casual: she gave a careless shrug

Derivatives

carelessly

adverb

Origin:

Old English carlēas 'free from care' (see care, -less)