biological shield

British

noun

a protective shield impervious to radiation, esp the thick concrete wall surrounding the core of a nuclear reactor

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

One of the central challenges is pouring the concrete – 3m tonnes in total – needed to build not only the massive foundations but also the vast biological shield around the reactor, which reduces the radiation to levels safe for humans.

From The Guardian

The more people who are vaccinated, the stronger the effect of herd immunity, which acts as a biological shield against communicable diseases for entire populations.

From Time

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023