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first-day cover

American  
[furst-dey, -dey] / ˈfɜrstˌdeɪ, -ˈdeɪ /

noun

Philately.
  1. a cover marked so as to indicate that it was mailed on the first day of issue of the stamp it bears and from one of the cities at which the stamp was issued on that day.


first-day cover British  

noun

  1. philately a cover, usually an envelope, postmarked on the first day of the issue of its stamps

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of first-day cover

First recorded in 1935–40

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A first-day cover service is being provided by the Royal Astronomical Society at a cost of 6s 6d.

From Nature

First-day cover collectors also have been frustrated with the agency’s new strategy of hiding details of upcoming new stamp releases until they are issued to the public, a move to generate excitement from buyers.

From Washington Post

A special first-day cover envelope showed an extract from his 1969 poem, Bogland.

From BBC

A drawing of him featured on a first-day cover sent in 1979 is coloured yellow.

From BBC