au ‧ da ‧ cious /ɔːˈdeɪʃəs $ ɒː-/ BrE AmE adjective
[ Date: 1500-1600 ; Language: French ; Origin: audacieux , from audace 'audacity' , from Latin audax 'brave' , from audere 'to dare' ]
showing great courage or confidence in a way that is impressive or slightly shocking:
the risks involved in such an audacious operation
—audaciously adverb