No-they do not expire. No US stamps issued since 1865 have been been devalued. The only exception are the special delivery stamps which paid for service no. longer offered. Air mail stamps are good for any purpose. Some stamps can't be used for certain things.
the pure and concentrated essence of a substance. 2. the most perfect embodiment of something. 3. (in ancient and medieval philosophy) the fifth essence or element, ether, supposed to be the constituent matter of the heavenly bodies, the others being air, fire, earth, and water. Origin of quintessence.
Wiktionary(0.00 / 0 votes)Rate this definition: quiche(Noun) A pie made primarily of eggs and cream in a pastry crust. Other ingredients such as chopped meat or vegetables are often added to the eggs before the quiche is baked. Quiche. Quiche is a savory, open-faced pastry crust with a filling of savory custard with cheese, meat, fish or vegetables.