badass(bad · ass) n., pl -es1. Someone who lives life free of any excuses they could make, no matter how legitimate those excuses may appear to be. 2. A person who doesn't say "I can't" even if everyone else is saying it. 3. A person who defines him- or herself by accomplishments, not limitations. 4. A person who realizes that there is always another way, and that almost nothing is impossible.