(Arab. forty), a word applied by the Mohammedans to denote the forty traditions. Mohammed promised that whosoever should teach the faithful to understand this number of -traditions, to instruct them in the way to heaven, should be exalted to the highest place in paradise. The consequence has been that Mohammedan doctors have collected an immense number of traditions in reference to the Mohammedan religion, which in their aggregate form bear the name of Arbain.