Bible Dictionaries
Postmark

Webster's Dictionary

(1):

(n.) The mark, or stamp, of a post office on a letter, giving the place and date of mailing or of arrival.

(2):

(v. t.) To mark with a post-office stamp; as, to postmark a letter or parcel.

Bibliography Information
Webster, Noah. Entry for 'Postmark'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​p/postmark.html. 1828.