noun.
A four-wheeled horse-drawn carriage having two or four seats.
The Century Dictionary and Cyclopedia
noun.
A light phaëton, with or without a top, and hung on side-bars with end-springs and with cross-springs extending from side to side, designed to carry four persons.
the GNU version of the Collaborative International Dictionary of English
noun.
A four-wheeled pleasure carriage, (commonly two-seated) somewhat like a phaeton, but having a straight bottom.