An Etymological Dictionary of the German Language/Annotated/Damm

by Friedrich Kluge

Damm, masculine, ‘dam, dike, mole,’ Middle High German tam(mm); the d of the Modern High German word compared with the t of Middle High German points to a recent borrowing from Low German; compare Dutch and English dam (a bank), Old Icelandic dammr. Gothic has only the derivative faurdammjan, ‘to embank, hinder’; akin to Anglo-Saxon demman, English to dam, Modern High German dämmen.