impossibility

Idioms (4)

• when pigs fly Informal · CEFR B1
  Used to say that something will never happen.
• grasp at straws Neutral · CEFR B2
  to try desperate, unlikely measures when things are going badly
• have your cake and eat it too Informal · CEFR B2
  to want two incompatible things at once
• out of the question Neutral · CEFR B1
  completely impossible or not permitted