sender

The sender put his holiday cards in the mailbox.
The definition of a sender is someone who caused something to be sent to a recipient.
An example of a sender is the person who put a letter in the mailbox.
sender

sender - Computer Definition

- Also known as a source or a transmitter, a sender is a device that originates, or generates, an information transfer to one or more receivers. See also receiver and transmitter.
- A component of an electromagnetic crossbar (Xbar) or panel switch, a sender receives dialed digits from a register or routing information from a translator, and sends the appropriate dialed digits across a trunk or to local station equipment. See also panel switch, register, translator, and Xbar.