mailcoach
US and Canadian mailcar
noun
a railway coach specially constructed for the transportation of mail
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Examples from the Web for mailcoach
Historical Examples of mailcoach
When the system of mailcoach lines reached its highest perfection, the mails were handled as they are today.
Historic Highways of America (Vol. 10)Archer Butler Hulbert