Prison

It shames me to admit it but I have absolutely no idea where the word "Prison" comes from. I thought about it and I can't come up with any etymological origin that would actually make sense.

Could it come from "to pry" and "Son". I don't see the link between a place where you lock people up and peeping on your son. Although I could see the former being the result of the latter.

I guess I could look it up on the interweb thing but I have to do other things that don't involve looking up the origin of the word "Prison" on the interweb, so... I will just file this case as unsolved.

Mystery unsolved.