Consignor
The consignor, in a contract of carriage, is the person sending a shipment to be delivered whether by land, sea or air. Some carriers, such as national postal entities, use the term “sender” or “shipper” but in the event of a legal dispute the proper and technical term “consignor” will generally be used.
If Sender sends a widget to Receiver via a delivery service, Sender is the consignor and Receiver is the consignee.
Wikipedia
Consigner (noun)
The party that consigns.
Consigner (noun)
The party that provides merchandise for consignment sale.
Consignor (noun)
The person who sends a consignment to a consignee.
Wiktionary