49 CFR 1244.1: Definitions.

(a) Railroad—an individual railroad or terminal company subject to the Interstate Commerce Act and every receiver, trustee, executor, administrator or assignee of any such railroad. If a railroad and its railroad subsidiaries report to the Board on a consolidated basis, they would collectively be considered as a railroad.

(b) A railroad subsidiary—a railroad owned or controlled by another railroad.

(c) A waybill, which may be referred to by other names such as mine tickets, is the document or instrument prepared from the bill of lading contract or shipper's instructions as to the disposition of the freight, and used by the railroad(s) involved as the authority to move the shipment and as the basis for determining the freight charges and interline settlements.