Pronunciation: rent'gen, rent'chen
The international unit of exposure dose for x-rays or gamma rays; that quantity of radiation that will produce, in 1 cc or 0.001293 g of air at STP, 2.08 × 109 ions of both signs, each totaling 1 electrostatic unit (esu) of charge; in the MKS system this is 2.58 × 10-4 coulombs per kg of air.
[Wilhelm K. Roentgen]
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Examples: glitazone, GI cocktail, etc.