1.
[syn: postcard, post card, postal card, mailing-card]
The Collaborative International Dictionary of English v.0.48:
Postal \Post"al\, a. [Cf. F. postal.]
Belonging to the post office or mail service; as, postal
arrangements; postal authorities.
[1913 Webster]
Postal card, or Post card, a card used for transmission
of messages through the mails, at a lower rate of postage
than a sealed letter; also called postcard. Such cards
are sold by the government with postage already paid, or
by private vendors without a postage stamp. The message is
written on one side of the card, and the address on the
other.
Postal money order. See Money order, under Money.
Postal note, an order payable to bearer, for a sum of money
(in the United States less than five dollars under
existing law), issued from one post office and payable at
another specified office.
Postal Union, a union for postal purposes entered into by
the most important powers, or governments, which have
agreed to transport mail matter through their several
territories at a stipulated rate.
[1913 Webster]
WordNet (r) 3.0 (2006):
post card
n 1: a card for sending messages by post without an envelope
[syn: postcard, post card, postal card, mailing-
card]