A Dictionary of Military Architecture.
   A dictionary of military architecture, fortification and fieldworks from the Iron Age to the eighteenth century by Stephen Francis Wyley.
   http://www.angelfire.com/wy/svenskildbiter/madict.html

Aaron's Illustrated Glossary of Architecture and Decor
   Architectural and related terms with illustrations and bibliography, hosted by Carnegie Mellon.
   http://www.contrib.andrew.cmu.edu/~ajm/Pages/

Architectural Terms
   An illustrated glossary by Alice Cotton.
   http://www.artemisillustration.com/assets/text/Ornamental%20%20Terms_Glossary.htm

Art and Architecture
   Single-page glossary of art and architectural terms, from Your Way to Florence.
   http://www.arca.net/tourism/glossary.htm

Art and Architecture Thesaurus
   A structured vocabulary from the Getty Trust of more than 125,000 terms for describing fine art, architecture, decorative arts, archival materials, and material culture.
   http://www.getty.edu/research/tools/vocabulary/aat/

Buffalo Illustrated Architecture Dictionary
   Indexed, cross-referenced and illustrated dictionary of architectural terms from Chuck LaChiusa. All examples are from buildings in Buffalo, New York.
   http://ah.bfn.org/a/DCTNRY/vocab.html

California Missions Studies Terms
   Illustrated glossary of terms relating to California missions and other Hispanic sites by Sasha Honig.
   http://www.ca-missions.org/illusgl.html

Castle Glossary
   A full glossary from Castles of Britain.
   http://www.castles-of-britain.com/castle38.htm

Glossary of Medieval Art and Architecture
   An illustrated and cross-referenced dictionary of mainly architectural terms from Jane Vadnal of the University of Pittsburgh.
   http://www.pitt.edu/~medart/menuglossary/

Landscape Gardening and Architecture
   A brief cross-referenced glossary of gardening and landscape-architecture terms by John D. Tatter, Birmingham-Southern College.
   http://panther.bsc.edu/%7Ejtatter/glossary.html

Looking at Buildings: Glossary
   An illustrated dictionary of architectural terms from the Pevsner Architectural Guides to the buildings of England, Ireland, Scotland and Wales.
   http://www.lookingatbuildings.org.uk/default.asp?document=2.30

The Conservation Glossary
   Architectural, building and conservation terms explained by Neil Grieve of The Centre for Conservation and Urban Studies, University of Dundee.
   http://www.trp.dundee.ac.uk/research/glossary/glossary.html