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noble gas

American  

noun

Chemistry.

  1. any of the chemically inert gaseous elements of group 8A or 0 of the periodic table: helium, neon, argon, krypton, xenon, and radon.

noble gas British  

noun

  1. another name for inert gas

"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
noble gas Scientific  
/ nō′bəl /

  1. Any of the six gases helium, neon, argon, krypton, xenon, and radon. Because the outermost electron shell of atoms of these gases is full, they do not react chemically with other substances except under certain special conditions.

  2. Also called inert gas

  3. See Periodic Table

Etymology

Origin of noble gas

First recorded in 1900–05

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.