An Etymological Dictionary of the German Language/Annotated/Dank

by Friedrich Kluge

Dank, masculine, ‘thanks, acknowledgment, recompense,’ from the equivalent Middle High German and Old High German danc, masculine; corresponds to Gothic þagks (þanks), Anglo-Saxon þanc, English thanks. Etymologically Dank is simply ‘thinking,’ hence ‘the sentiment merely, not expressed in deeds.’ See denken; dünken.