Denshi Jisho — Online Japanese dictionary

大胆 だいたん bold; daring; audacious
Common word, Na-adjective, Noun 
大胆至極 だいたんしごく the height of daring; very courageous (reckless), extremely audacious
Noun, Na-adjective 
大胆不敵 だいたんふてき audacity; daredevil (attitude)
Na-adjective, Noun 
大胆奔放 だいたんほんぽう bold and unrestrained; daring and unfettered
Noun, Na-adjective, No-adjective 
大胆巧妙 だいたんこうみょう bold and clever; daring and ingenious; audacious and masterly
Noun, Na-adjective 

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