facinorous /fəˈsɪnəɹəs/ adjective1 •(formal, no longer used) Extremely wicked.Tru. I would kill you, Sir, I would kill you, if you had. Mor. Why? you do more in this, Sir: it were a vengeance centuple, for all facinorous Acts, that could be nam'd, to do that you do. formsmore facinorous · most facinorous