relative biological effectiveness

relative biological effectiveness

n.

A measure of the capacity of a specific ionizing radiation to produce a specific biological effect, expressed relative to a reference radiation, such as radium gamma rays or 200-volt x-rays.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

relative biological effectiveness

The ratio of the number of rads of gamma (or X) radiation of a certain energy that will produce a specified biological effect to the number of rads of another radiation required to produce the same effect measures the "relative biological effectiveness" of the latter radiation.

Dictionary of Military and Associated Terms. US Department of Defense 2005.