noun
1. : short-term negotiable instruments (as bills of exchange, checks, and promissory notes) arising out of commercial transactions ; especially : instruments constituting direct obligations of business firms that are sold through note brokers to banks, corporations, and other investors seeking liquid investments
2. commercial papers plural , in Universal Postal Union regulations : pieces of mail matter in a classification comprising business papers and documents and including old correspondence, invoices, and bills of lading that have previously served their purpose and are not at the time of shipment being sent as current personal correspondence