What is "human"?

Beep★★★™ • Uppity blacktivist ✊🏼 #BLM, & social deviant; I'll spare you the whole Megillah 😉 The Revolution will not be televised
How do YOU define "human"? 
As technology progresses and we begin to explore the human as a design space, where is the boundary for being considered human? 
If an organic brain is in a mechanical body, is it human?
If a mechanical brain is in an organic body could we consider that human?
People that depend on devices such as pacemakers to keep them alive, people with "smart" prosthetics, does their immediate dependency on that technology make them less human?