1. mod. courageous; daring; foolhardy. (Usually said of a male. Usually objectionable.)□ Who is that ballsy jerk climbing the side of the building?2. mod. aggressive; masculine. (Said of a female, especially a masculine female. Usually objectionable.)□ You act too ballsy, Lillian. You put people off.
Dictionary of American slang and colloquial expressions. 2015.