1. a unit of measurement for X-rays and gamma rays
Usage: physics; medical

Examples

• The technician measured the radiation exposure in roentgens.
• A chest X-ray typically exposes patients to about 0.1 roentgens.
• The roentgen was named after Wilhelm Roentgen, who discovered X-rays.
• Safety regulations limit workers to 5 roentgens per year.
• The Geiger counter detected 50 roentgens per hour near the source.
• Medical equipment must be calibrated to measure roentgens accurately.