red-out
n.— «The scope should not be advanced against resistance. “Red-out” is the term used to describe what occurs when the tip of the scope is placed too close to the bowel wall mucosa. In this situation, the reflection of light off the vascularized tissue produces a red haze. By slightly withdrawing the scope, the endoscopist can again obtain a clear view of the bowel wall.» —“Health: Screening for Colorectal Cancer” Ghana News Oct. 9, 2008. (source: Double-Tongued Dictionary)
Further reading
Outer space, used with its modern meaning, appears as early as the 1840s in a poem by Emmeline Stuart-Wortley. Soon after, Alexander von Humboldt was using variations on it in his writings about the cosmos. By 1901, H.G. Wells was using outer space...
Aaron in Los Angeles, California, notes while using public transit in Britain he and other passengers were instructed to alight from the front, meaning “exit the car from the front.” Alight comes from an Old English word alihtan, literally, to...