lie ill in one's mouth

Meanings:

• 1.

  BritishAmericanarchaicliterary
  • To be disagreeable or embarrassing to say; to sit uncomfortably on the tongue when spoken.
  • To be distasteful or unpleasant to acknowledge or express.

• 2.

  BritishAmericanarchaismsfigurative
  • Figuratively, to cause moral discomfort or shame when stated aloud.