Philosophy Research Guide: DICTIONARIES & GLOSSARIES

The British Library's Glossary for Illuminated Manuscripts is a free online resource, and is now fully illustrated with examples from their large collection. 

Their Digital Catalogue of Illuminated Manuscripts can be found here.

From USC Libraries Medieval Studies & Research Guide by Dr. Danielle Mihram & Dr. Melissa Miller

The Project for American and French Research on the Treasury of the French Language (ARTFL) - A collaboration between the French government and the University of Chicago

Dictionary of Middle French - A collaboration between the National Center for Scientific Research and the University of Lorraine

The Etymological Dictionary of Old French (DEAF) - Presented by the Heidelberg Academy of Sciences

Abreviaturas en paleografía - Abbreviations in Paleography

Pan-Hispanic Dictionary - Presented by the Royal Spanish Academy.

Digital Dictionary of Novohispanic Abbreviations - Presented by Universidad Nacional Autónoma de México (UNAM)

Dictionary of the Spanish Language - Presented by the Royal Spanish Academy.

Medieval Portuguese Dictionary - Provided by the Linguistics Center at NOVA University of Lisbon

Tesoro de la Lengua Castellana o Española - from the Library of the University of Sevilla

The Dictionary of Old English (DOE) - Presented by the University of Toronto

The Anglo-Norman Dictionary - Presented by Aberystwyth University

Bosworth-Toller's Anglo-Saxon Dictionary Online - Hosted by the Faculty of Arts, Charles University

Lexilogos Middle English Online Dictionary - Lexilogos is a comprehensive set of resources for the study of the languages of the world.

The Digital Latin Library (DLL) is a joint project of the Society for Classical Studies, the Medieval Academy of America, and the Renaissance Society of America. The Andrew W. Mellon Foundation's Scholarly Communications Program funds the project, and the University of Oklahoma hosts it.

Logeion (literally, a place for words; in particular, a speaker's platform, or an archive) was developed after the example of dvlf.uchicago.edu, to provide simultaneous lookup of entries in the many reference works that make up the Perseus Classical collection.

Dictionary of Medieval Latin from British Sources is a British Academy research project at the University of Oxford. Based entirely on original research, the DMLBS is the most comprehensive dictionary of Medieval Latin to have been produced and the first ever to focus on British Medieval Latin.

Dictionary of Medieval Latin from Celtic Sources is an integrated database and dictionary project, designed to contribute to the fields of Patristic, Medieval, Celtic, and Latin studies by compiling and publishing suitable scholarly works, both in electronic and in conventional media.

Also Available Online, provided by the University of Zurich.

From USC Libraries Medieval Studies & Research Guide by Dr. Danielle Mihram & Dr. Melissa Miller