fatal or fateful? These two words are sometimes confused. Fatal means ‘causing or resulting in death’: a fatal accident or ‘causing ruin; ending in disaster’: a fatal mistake. Fateful means ‘momentously important’: their fateful meeting. In the sense of ‘having significant, often unpleasant consequences’ either word may be used, although fateful is more usual: that fateful day. Care should be taken to avoid misinterpretation: a fateful experiment may change lives; a fatal experiment may lead to death