• 駑鈍どどん

  dull-witted, stupid, foolish

• 駑馬どば

  hack, inferior horse

• 駑馬に鞭打つどばにむちうつ

  to work hard, to keep one's nose to the grindstone, to whip a jaded horse

• 麒麟も老いぬれば駑馬に劣るきりんもおいぬればどばにおとる

  even an outstanding person becomes inferior when getting old