Cobra any of various species of venomous snakes usually belonging to the family Elapidae, most of which can expand their neck ribs to form a widened hood. Not all snakes commonly referred to as cobras are of the same genus, or even of the same family. The name is short for cobra de capelo or cobra-de-capelo, which is Portuguese for "snake with hood", or "hood-snake". When disturbed, most of these snakes can rear up and spread their necks (or hoods) in a characteristic threat display, making them a favorite of snake charmers because of this stunning appearance. Long ago, snake charming used to be a religious ritual, though nowadays it has become an entertainment. Cobras, which may live up to 20 years, are found from southern Africa, through southern Asia, to some of the islands of Southeast Asia.