Philatelic Glossary
This glossary has been compiled from various different sources. Some of the terms have been reproduced with kind permission from the Stanley Gibbons Philatelic Terms Illustrated by James Mackay. If you think a term is missing please e-mail us.
U-Boat Mail
Mail carried by German Submarines during both world wars.
Ultra Violet Light
q.v Quartz Lamp
Ultramer
Overprint applied at Lisbon to stamps distributed by the UPU for Portuguese Colonies
Unappropriated Die
Die used to produce many British fiscal and revenue stamps.
Uncatalogued
Known to exist but not listed in any catalogue.
Undenominated Stamps
Stamps which do not show a face value.
Underprint
An underprint refers to inscriptions on the back of a stamp.
Undivided Back
Postcard without the dividing line to separate the message section from the address.
Unemployed Intellectuals Stamps
Stamps issued by France between 1935 and 1940 with a premium in aid of the unemployed.
Ungummed Stamps
Postage stamps issued without gum on the back.
Unhinged
Stamps without any trace of a hinge mark.
Uniform Fourpenny Post
From 5 December 1839 to 9 January 1840 letters posted in GB were charged a uniform rate of 4d instead of postage calculated by distance.
Uniform Penny Post
Started in GB on 10 January 1840 with a basic rate of 1d per half ounce regardless of distance carried, discontinued in 1918.
Uniform Postage
A postal system whereby mail is conveyed at a flat rate irrespective of distance or any other factor apart from weight.
Unissued Stamps
Stamps which have been prepared for issue but for some reason have not been issued for postal use.
Universal Colours
Colours adopted by members of the UPU for stamps prepaying three classes of postal service: green basic foreign printed matter, red internal postcards, blue internal single rate letters. The use of these colours was ignored by many countries and abandoned by the UPU in 1953.
Universal Postal Union (U.P.U.)
International organisation with its headquarters in Berne which is responsible for co-ordinating international mail.
Unlisted
A stamp which does not appear in a stamp catalogue.
Unmounted Mint
Stamps in perfect condition as issued by the Post office.
Unofficial Stamps
Stamps issued by bus, airline and shipping companies to prepay charges on their parcels and packets.
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