Þeudō

Theodiscus is a Medieval Latin term literally meaning "popular" or "of the people". In Medieval Western Europe non-native Latin was the language of science, church and administration, hence theodiscus was used as an antonym of Latin, to refer to the "native language spoken by the general populace". The term was subsequently used in the Frankish Empire to denote the native Germanic vernaculars. As such, it was no longer used as antonym of Latin, but of walhisk, a language descendent from Latin, but nevertheless the speech of the general populace as well. In doing so theodiscus effectively obtained the meaning of "Germanic", or more specifically one of its local varieties – resulting in the English exonym , the German endonym , and the Dutch exonym , all of which are all cognates of theodiscus.

Theodiscus is derived from West Germanic *þiudisk, from Proto-Germanic . The stem of this word, , meant "people" in Proto-Germanic, and was an adjective-forming suffix, of which is the Modern English cognate with the same meaning. The Proto-Indo-European word ("tribe", "people"), which is commonly reconstructed as the basis of the word, is related to Lithuanian ("nation"), Old Irish ("tribe", "people") and Oscan touto ("community").

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