mail franked privately, under licence, with a machine bearing special markings (meter marks)
metered mail in American English
noun
mail on which the postage is printed directly on an envelope or label by a machine licensed by the postal service
Word origin
[1925–30]This word is first recorded in the period 1925–30. Other words that entered Englishat around the same time include: Nazi, gimmick, hot spot, payload, runout