Postcard
来自Big Physics
wiktionary
post + card
etymonline
postcard (n.)
1870, "a stamped blank card provided by postal authorities for writing and mailing short messages at a less rate of postage than that charged for letters," from post (n.3) + card (n.1). By 1894 it was being used in reference to private, blank, or unofficial cards, unstamped, of the same size, often with a picture on one side.
