An Etymological Dictionary of the German Language/Annotated/Wacke

by Friedrich Kluge

Wacke, feminine, ‘wacke, toadstone,’ from Mid High German wacke, masculine, ‘rock-flint, block of stone projecting from the ground,’ Old High German *wacko- (from the base waggo), masculine, ‘pebble, flint.’ Further cognates are wanting.