Lettercard

In philately a lettercard or letter card is a postal stationery item consisting of a folded card with a prepaid imprinted stamp. The fact that it is folded over gives the writer twice as much room for the message compared with a postal card. The message is written on the inside and the card is then folded and sealed around the edges. The recipient...
Found on http://en.wikipedia.org/wiki/Lettercard

lettercard

noun a postcard that folds so the message is inside
Found on https://www.encyclo.co.uk/local/20974

lettercard

[n] - a postcard that folds so the message is inside
Found on http://www.webdictionary.co.uk/definition.php?query=lettercard
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