A stamp or stationery item that has been canceled by a postal authority to prevent its reuse on mail. In general, a used stamp is any stamp with a cancel or a precanceled stamp without gum. See also Postally Used and Philatelic Cover.
A stamp which has been postally used and appropriately postmarked.
The term denotes a stamp that has been postally used rather than canceled to order.
a stamp which has been cancelled
Stamps which have fulfilled their intended duty, carried a piece of mail.
The condition of a stamp that has been canceled.
implies a stamp postally used, normally cancelled, and in fair to good condition. See Mint.