[ doo-teer-ee-uhm, dyoo- ]

  1. an isotope of hydrogen, having twice the mass of ordinary hydrogen; heavy hydrogen. Symbols:2H, D; atomic weight: 2.01; atomic number: 1.

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Origin of deuterium

1933; <Greek deúter(os) second (see deutero-) + -ium

Words Nearby deuterium Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use deuterium in a sentence

British Dictionary definitions for deuterium


/ (djuːˈtɪərɪəm) /

  1. a stable isotope of hydrogen, occurring in natural hydrogen (156 parts per million) and in heavy water: used as a tracer in chemistry and biology. Symbol: D or ²H; atomic no: 1; atomic wt: 2.014; boiling pt: –249.7°C

Origin of deuterium

C20: New Latin; see deutero-, -ium; from the fact that it is the second heaviest hydrogen isotope

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

Scientific definitions for deuterium


[ dōō-tîrē-əm ]

  1. An isotope of hydrogen whose nucleus has one proton and one neutron and whose atomic mass is 2. Deuterium is used widely as a tracer for analyzing chemical reactions, and it combines with oxygen to form heavy water. Also called heavy hydrogen See Note at heavy water.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.