overfierce UK /ˌəʊvəˈfɪəs/US /ˌoʊvɚˈfɪɹs/ adjective1 •(rare) Excessively fierce; overly ferocious.In other respects also his book is a severe and overfierce indictment against the century for its still-continued failures and its wonderful achievements and correspondingly wonderful advantages. — 1898 formsmore overfierce · most overfierce