Military

Argos Press Radar Glossary
Describes key terms and abbreviations used in radar and electronic warfare.
http://www.argospress.com/Resources/radar/

Army Technology Glossary
Glossary of military terminology and phrases associated with modern armoured warfare.
http://www.army-technology.com/contractors/publications/glossary.html

Army Technology Glossary
Glossary of military terminology and phrases.
http://www.army-technology.com/glossary/

Artillery Glossary
Illustrated glossary of artillery-related terms.
http://www.civilwarartillery.com/glossary/glossary.htm

British Military Slang
Military terms and soldier slang used historically in the British military.
http://www.geocities.com/faskew/Colonial/Glossary/British.htm

DOD Dictionary of Military Terms
Acronyms, abbreviations and terms searchable by definition and usage of individual terms.
http://www.dtic.mil/doctrine/jel/doddict/

Grunt
Glossary of military terms and acronyms.
http://www.geocities.com/Pentagon/5688/mildic.htm

Medieval Weapons
Weapons terms with separate glossaries for archery and projectiles, light, and heavy weapons as well as a non-combat and general terms glossary.
http://www.realtime.net/~otto/handbook/bookglos.html

Military Architecture
Illustrated and cross-referenced dictionary of military architecture terms used in fortification and fieldworks from the Iron Age up until the eighteenth century.
http://www.angelfire.com/wy/svenskildbiter/madict.html

Military Lexicon
Dictionary of acronyms, initialisms, abbreviations and general military terminology.
http://www.fas.org/news/reference/lexicon/mildef.htm

Military Spending
Brief glossary of key terms related to military spending.
http://www.cdi.org/issues/glossary.html

NATO Terms
United States Department of Defense dictionary of Nato-specific military and associated terms.
http://www.dtic.mil/doctrine/jel/doddict/natoterm_index.html

Nomenclature of Naval Vessels
Includes index list of naval terms maintained by the United States Department of the Navy circa 1942.
http://www.ibiblio.org/hyperwar/USN/ref/NNV/USN-NNV_ABC.html

World War II U-boat Terms
Cross-referenced glossary of German U-Boat terminology.
http://uboat.net/special/glossary_list.htm