swallow one's words

/S W AA1 L OW0 W AH0 N EH0 S W ER0 D Z/
verb
  1. 1

    To be forced to retract a prior statement after it has been shown to be disproven; to take back what one has said.

  2. 2

    To speak at a low volume due to uncertainty about one's speech; to mumble.