dictionary covering the historical development of forms and meanings of words
A historical dictionary or dictionary on historical principles is a type of dictionary which deals not only with the present-day meanings of words but also the historical development of their forms and meanings. It may also describe the vocabulary of an earlier stage of a language's development without covering present-day usage at all. A historical dictionary is primarily of interest to scholars of language, but may also be used as a general dictionary or by those who are interested in understanding a word's development over time.
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