1 [count] a : a small piece of paper that you buy and then stick to an envelope or package to pay the cost of mailing it
▪ a 39-cent stamp —called also postage stamp; — see picture at mail
b : a small piece of paper that is attached to something and that shows that a tax or fee has been paid — see also food stamp 2 [count] a : a device or tool that is used to mark something (such as a piece of paper) with a design, pattern, word, etc., by being pushed against a surface : a device or tool used for stamping something — see also rubber stamp
b : the mark made by a stamp
▪ There was a stamp on the letter showing the date when it was received. 3 a [singular] : a sign of a special or specific quality — usually + of ▪ Her poetry bears the stamp of genius. ▪ His quiet manner gives/lends his words the stamp of authority. [=makes his words seem authoritative]
b [count] : an indication of something — usually singular ▪ She gave the plan her stamp of approval. [=she approved the plan]
c [singular] : an important or lasting effect
▪ He put/left his stamp on the process. [=he affected/changed the process in some important way] 4 [singular] literary : a particular kind or type
▪ He was a man of a different stamp. [=he was a different sort of man] 5 [count] : the act of bringing your foot down heavily and noisily
▪ an angry stamp of his foot