Dictionary
post•mark
Pronunciation: (pōst'märk"), [key]—
n.
an official mark stamped on letters and other mail, serving as a cancellation of the postage stamp and indicating the place, date, and sometimes time of sending or receipt.
—
v.t.
to stamp with a postmark.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.