An Etymological Dictionary of the German Language/Kaldaunen
Kaldaunen, f. plur., ‘intestines,’ from MidHG. and MidLG. kaldûne; a MidHG. and LG. word (in UpG. Kutteln). It is based upon a Rom. and MidLat. caldûmen, a derivative of Lat. calidus (caldus) ‘warm,’ meaning chiefly ‘the still reeking entrails of newly slaughtered animals’; comp. South-West Fr. chaudin, Bologn. caldôm, ‘entrails.’ From East Rom. (and G.?) the word found its way also into Slav.; comp. Czech kaldoun, ‘entrails,’ Croat. kalduni, ‘lung.’