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.
OHMS
On Her (His) Majesty's Service
Omnibus Issues
Sets of stamps in a common design as those issued in several territories simultaneously and only differing in the names of the countries and the values inscribed on them.
On Paper
Term for adhesive stamps which have been cut from envelopes and are still attached to their paper backing. Also known as Kiloware (q.v).
On Piece
An adhesive stamp on part of an envelope which usually shows the complete postmark or other information.
Opt
Overprint
Optical Character Recognition (OCR)
Equipment which reads handwritten or printed material i.e an address on an envelope or similar.
Orb Watermark
Representation of part of the British Regalia showing the globe surmounted by a cross used as a watermark device.
Original
A term used to denote a stamp officially issued for postal use as opposed to a reprint.
Original Coated Paper
Paper which is off white, prior to late 1971 on which machin (q.v) stamps were printed.
Original Gum
A stamp which still possesses all or some of the gum with which it was issued.
Out of Register
One or more colours in printing being out of alignment with the others.
Outward Vouching Office
A mail centre where mail for a postcode district is processed.
Overland Mail
Term for mail on any route across western Asia.
Overlay
Packing substance used in relief printing (letterpress) to ensure that proper pressure is applied to each part of the stamp's design at the time of printing.
Overnight Delivery Stamps
High value stamps issued in USA to prepay special handling fees on express packets sent overnight.
Overprint
An additional feature or inscription applied to the face of a stamp after basic production has been completed.
Overseas Dominions Essay
Printer's sample stamp produced by De La Rue to solicit orders from prospective customers.
Oxidised
Stamps whose colour was originally red, yellow or orange which have turned deep brown or black due to atmospheric pollution.
OXO Postmark
One of the obliterators used to cancel British forces mail in the Crimean war (1854-57).
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