eat one's words

発言を撤回する, 自分の過ちを認める

After confidently predicting the rival's defeat, he ultimately had to eat his words when their underdog team triumphed unexpectedly.

対戦相手の敗北を自信満々に予想した後、実力の低いチームが予想外に勝利したため、彼は自分の言葉を飲み込まざるを得なかった.