An ill-fated day is one you remember for years as extremely unlucky, and an ill-fated decision, in retrospect, was a really bad choice. An ill-fated attempt at tightrope walking results in falling off over and over again, and an ill-fated choice of lunch in a foreign country might end in food poisoning. Ill-fated is rooted in ill-, "badly," and fated, "be destined to happen," from the Latin fatum, "that which has been spoken."