The definition of "magic" by todays standards (according to Webster) is:
Mag·ic \'maj-ik\ n. 1) The art of persons who claim to be able to do things by the help of supernatural creatures or by their own knowledge of nature's secrets. 2) Something that charms; any seemingly hidden or secret power; as, the magic of a voice; the magic of a great name. 3) Sleight of hand. -adj. 1) Of or having to do with magic. 2) Seemingly requiring more than human power; startling in performance; producing effects which seem supernatural; as, magic skill. 3) Having the powers or effects of magic; as, a magic land or scene. |
From Wikipedia
Magic is a performing art that entertains an audience by creating illusions of impossible[1] or supernatural[2] feats, using purely natural means. These feats are called magic tricks, effects or illusions.