postmark; cancellation mark
The mark stamped on a postal item to cancel the stamp and record the date and place of mailing.
封筒の消印を見ると、昨日の日付だった。
Looking at the postmark on the envelope, it was dated yesterday.
This stamp has a clear cancellation mark on it.
The postal worker stamped a postmark on the envelope.
Applications are valid if postmarked by the end of May.
This postcard has a Tokyo postmark on it.