This dictionary is an indispensable guide to the study of the Latin Middle Ages. Though it records the usage of Classical and Late Latin current in this period (6th-16th centuries), it presents most fully the medieval developments of the language as revealed in a rich variety of printed and manuscript sources. Many new formations from other languages are revealed ? some of the borrowings here recorded in Latin centuries before their appearance in written vernacular sources.

It is now intended that fascicules will be slimmer than before and will appear more frequently. This sixth fascicule, devoted to just the letter M, is the first in the new format.