Post"mark` (?), n.
The mark, or stamp, of a post office on a letter, giving the place and date of mailing or of arrival.
© Webster 1913.
Post"mark`, v. t. [imp. & p. p. Postmarked (?); p. pr. & vb. n. Postmarking.]
To mark with a post-office stamp; as, to postmark a letter or parcel.
© Webster 1913.