

The name is derived from its propensity to eat snakes. The genus Ophiophagus was proposed by Günther in 1864.

Hamadryas elaps proposed by Albert Günther in 1858 were king cobra specimens from the Philippines and Borneo. Naia vittata proposed by Walter Elliot in 1840 was a king cobra caught offshore near Chennai that was floating in a basket. In 1838, Cantor proposed the name Hamadryas ophiophagus for the king cobra and explained that it has dental features intermediate between the genera Naja and Bungarus. Naja bungarus was proposed by Hermann Schlegel in 1837 who described a king cobra zoological specimen from Java. Hamadryas hannah was the scientific name used by Danish naturalist Theodore Edward Cantor in 1836 who described four king cobra specimens, three captured in the Sundarbans and one in the vicinity of Kolkata. The king cobra is also referred to by the common name " hamadryad", especially in older literature. Regarded as the national reptile of India, it has an eminent position in the mythology and folk traditions of India, Bangladesh, Sri Lanka and Myanmar. Threatened by habitat destruction, it has been listed as Vulnerable on the IUCN Red List since 2010. Bites from this species are medically significant which may result in a rapid fatality unless antivenom is administrated in time. Despite its fearsome reputation, altercations usually only arise from an individual inadvertently exposing itself or being chased if, however, provoked or cornered, it is capable of striking long in range and high in position. The threat display of this elapid includes spreading its neck-flap, raising its head upright, making eye contact, puffing, hissing and occasionally charging. A female king cobra builds a nest to hold its eggs which will be protected throughout the incubation period. The king cobra inhabits forests from South to Southeastern Asia where it preys chiefly on other snakes, including those of its kind. The sole member of the genus Ophiophagus, it is not taxonomically a true cobra, despite its common name and some resemblance. Colouration of this species varies across habitats, from black with white stripes to unbroken brownish grey. With an average length of 3.18 to 4 m (10.4 to 13.1 ft) and a maximum record of 5.85 m (19.2 ft), it is the world's longest venomous snake. The king cobra ( Ophiophagus hannah) is a venomous snake endemic to Asia.

Hamadryas Cantor, 1836 ( non Hübner, 1804: preoccupied).
