(as) pale as a ghost
Exceptionally pale, as due to nausea or fear. I get terrible motion sickness, so I'm sure I was as pale as a ghost when I stumbled off the plane. She was pale as a ghost after that car nearly ran into her on the sidewalk.
*pale as a ghost
and *pale as deathvery pale. (*Also: as ~.) Laura came into the room, as pale as a ghost. "What happened?" her friends gasped. What's the matter? You're pale as death!