The verbs founder and flounder are often confused. Founder comes from a Latin word meaning “bottom” (as in foundation) and originally referred to knocking enemies down; it is now also used to mean “to fail utterly, collapse.” Flounder means “to move clumsily, thrash about,” and hence “to proceed in confusion.” If John is foundering in Chemistry 1, he had better drop the course; if he is floundering, he may yet pull through.