RhymeZone: paquebot definitions

Definitions of paquebot:

noun: a mailboat
noun: (postal history) a postal marking or cancellation stamped on mail posted at sea or in a harbour for processing by the postal authorities at the next port of call. Mail so marked in one country will often carry the stamps of another country.
adjective: Relating to mail posted at sea.

(Definitions from Wiktionary)