Châryâka (Sk.) There were two famous beings of this name. One a Rakshasa (demon) who disguised himself as a Brâhman and entered Hastinâ-pura; whereupon the Brahmans discovered the imposture and reduced Châryâka to ashes with the fire of their eyes,—i.e., magnetically by means of what is called in Occultism the “black glance” or evil eye. The second was a terrible materialist and denier of all but matter, who if he could come back to life, would put to shame all the “Free thinkers” and “Agnostics” of the day. He lived before the Râmâyanic period, but his teachings and school have survived to this day, and he has even now followers, who are mostly to be found in Bengal.
Source: H.P.Blavatsky - The Theosophical Glossary