Meaning of redout

red•out

Pronunciation: (red'out"), [key]
— n.
  1. a condition experienced by pilots and astronauts in which blood is forced to the head and results in a reddening of the field of vision during rapid deceleration or in maneuvers that produce a negative gravity force.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.