ENIGMA, denotes any dark saying, wherein some well-known thing is concealed under obscure language. The word is Greek, Enigma, formed of en, in, obscure, innuere, to hint a thing darkly, and of ma, an obscure speech or discourse. The popular name is riddle; from the Belgic raeden, or the Saxon oræthan, to interpret. F. Bouhours, in the memoirs of Trevoux, defines an enigma, a discourse or painting, including some hidden meaning, which is proposed to be guessed.