v. 1. [techspeak] To transfer programs or data over a digital communications link from a smaller or peripheral 'client' system to a larger or central 'host' one. A transfer in the other direction is, of course, called a download (but see the note about ground-to-space comm under that entry).
2. [speculatively] To move the essential patterns and algorithms that make up one's mind from one's brain into a computer. Only those who are convinced that such patterns and algorithms capture the complete essence of the self view this prospect with gusto.