unhuman

[in-hyoo-muh n, or, often,, ‐yoo-muh n ]

adjective

lacking human attributes: The unhuman figures in his earlier work were not well received.
of a quality or power beyond what is human; superhuman: Her hands clenched the chair with unhuman strength.
not a member of the human species: Of our unhuman relatives, I love the mountain gorillas best.

Origin of unhuman

First recorded in 1780–85; un-¹ + human

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Hemmed in by the crowd, he could but face me; he did so with a kind of unhuman passivity.
The Million-Dollar Suitcase
Alice MacGowan
It was a curious sound, loud and hollow and unhuman, yet it seemed to be a cough.
Short Stories of Various Types
Various
Why, that's the most unhuman thing I ever heard of in all my life!
The Admiral's Caravan
Charles E. Carryl
But neither ancient gentleman could convince me that you are unhuman.
The Thing from the Lake
Eleanor M. Ingram
Desire of mine and of the unhuman Thing, did we grasp at Eve or Lilith?
The Thing from the Lake
Eleanor M. Ingram

1540s, "inhumane, cruel," from un- (1) "not" + human. Meaning "superhuman" is from 1782.