Superhuman, a.
Above or beyond what is human; sometimes, divine; as, superhuman strength; superhuman wisdom.
Shades of meaning
Fernald has no entry of its own for superhuman; he lists it under supernatural.
Where he writes about it:
All that is beyond human power is superhuman; as, prophecy gives evidence of superhuman knowledge; the word is sometimes applied to remarkable manifestations of human power, surpassing all that is ordinary. — from supernatural