What is a Genius ?
genius (n.) late 14c., "tutelary or moral spirit" who guides and governs an individual through life, from Latin genius "guardian deity or spirit which watches over each person from birth; spirit, incarnation; wit, talent;" also "prophetic skill; the male spirit of a gens," originally "generative power" (or "inborn nature"), from PIE gen(e)-yo-, from root gene- "give birth, beget," with derivatives referring to procreation and familial and tribal groups. Sense of "characteristic disposition" of a person is from 1580s.
Meaning "person of natural intelligence or talent" and that of "exalted natural mental ability" are first recorded 1640s.
© from www.etymonline.com