Historical and comparative linguistics has been a major scholarly discipline for 200 years, and yet this is the first dictionary ever devoted to it. With nearly 2400 entries, this dictionary covers every aspect of the subject, from the most venerable work to the exciting advances of the last few years, many of which have not even made it into textbooks yet. All of the traditional terms are here, but so are the terms only introduced recently, in connection with such varied subjects as pidgin and creole languages, the sociolinguistic study of language change, mathematical and computational methods, the novel approaches to linguistic geography, the controversial proposals of new and vast language families, and the attempts at relating the results of the historical linguists to those of the archaeologists, the anthropologists and the geneticists. More than just a dictionary, this book provides genuine linguistic examples of most of the terms entered, detailed explanations of fundamental concepts, critical assessment of controversial ideas, cross-references to related terms, and an abundance of references to the original literature. Features: *The first dictionary in the field. *Comprehensive coverage. *Clearly written and accurate entries. *Covers traditional and contemporary terminology. *Provides linguistic examples of terms defined. *Supplies numerous cross-references to related terms. *Includes hundreds of references to the original literature.