- last post: 01.01.0001 12:00 AM PDT
He actually is a cyborg.
cy·borg
A human who has certain physiological processes aided or controlled by mechanical or electronic devices.
- - - -dictionary.com
The mjolnir suit, + Cortana (most of the time), either of these makes him a cyborg. He is still human. Also, this is confirmed in the books.