The term that I use to describe this union is 'cyborg' but I guess anybody with an artificial leg or a hook in place of there hand could be called cyborgs. But I want to dive in a bit farther (I would like to hear other peoples oppinions about when a person starts to become actualy 'part machine') but I tend to think that the line gets crossed when the machine part starts automaticaly thinking for a person, so in my mind most people are a few steps removed from being classified as cyborgs but they are almost connected to there smart phone (I think that smart phones have made some people mentaly lazy)
But I think that @spirajn might enjoy this conversation.