An Etymological Dictionary of the German Language/Annotated/Thür

by Friedrich Kluge

Thür, feminine, ‘door,’ from the equivalent Middle High German tür, Old High German turi, feminine; properly a plural form, the idea being often expressed by such a form; in Old High German we find turi as plural with a singular meaning (the stem was really dur-). Corresponding to Old Saxon duri (dura), Dutch deur, Anglo-Saxon duru (dyre); Old Icelandic dyrr is plural only. The common Aryan stem dhur (dhwer) recurs in Greek θύρα, θύρετρον, ‘door,’ to which θαιρός, ‘hinge of a door,’ and θυρών, ‘vestibule’ (compare Gothic daurôns, plural only, ‘door’), are allied; Latin fores, ‘door,’ Old Slovenian dvĭrĭ, ‘door’ (dvorŭ, ‘court’), Lithuanian dùrys, ‘door.’ To these are allied the equivalent Sanscrit dur, dvâr, which in the oldest period was inflected only in the dual or plural (the initial aspirate is dropped, because the case suffix begins with an aspirate). The primary meaning of this word, which has invariably the Modern High German signification, cannot be discovered. Allied to Thor.