Definition of "uplink"

The portion of a communications link used for the transmission of signals from an Earth terminal to a satellite or to an airborne platform. An uplink is the converse of a downlink. An uplink or downlink is distinguished from reverse link or forward link.  examples

(by analogy, less formally) The communication path from a mobile device to a base station, a consumer to the network backbone, a client device to a server etc.  examples

Data transmission from a data station to the headend.  examples

To transmit a signal by means of an uplink.  examples