means A small rectangular card, often bearing a picture on one side, sent through the mail without an envelope and carrying a short message that anyone handling it could read.

from A transparent compound of "post" and "card." "Post" comes through French from Latin *positus*, "placed," via the relay stations where horses and messengers were "placed" along a route — the same root behind the postal system itself. "Card" traces back through French *carte* to Latin *charta*, "a leaf of papyrus or paper." The thing arose in the latter half of the 19th century, when postal services began allowing open cards to travel at a cheaper rate than sealed letters — the picture-postcard craze followed once printers realized a blank back was an invitation for a holiday view.