An Etymological Dictionary of the German Language/Annotated/räuspern
räuspern, verb, ‘to hawk, clear the throat,’ from the equivalent Middle High German riuspern (riustern). This verb, which is not recorded prior to Middle High German, belongs to a root frequently occurring in Teutonic, rū̆k (Aryan rū̆g), ‘to belch, eructate,’ the k disappearing before the suffix sp, st; compare Anglo-Saxon roccettan, ‘to belch,’ Old High German itarucchen, Middle High German itrücken, Anglo-Saxon edorcan (eodorcan), ‘to chew the cud.’ Compare Latin ê-rûgere, ‘to spit out,’ rûminare (for *rûgminare), ‘to chew the cud,’ and ructare, ‘to belch,’ Greek ἐρεύγεν, ‘to spit out,’ ἐρυγή, feminine, ‘vomiting,’ Old Slovenian rygati sę ‘to belch,’ Lithuanian atrūgas, feminine plural, ‘rising of the stomach.’