deuterium

noun

deu·​te·​ri·​um dü-ˈtir-ē-əm 

 also  dyü-

: an isotope of hydrogen that has one proton and one neutron in its nucleus and that has twice the mass of ordinary hydrogen

—symbol D

called also heavy hydrogen

Examples of deuterium in a Sentence

Recent Examples on the Web

The reaction between deuterium and helium-3 would expel protons, and their positive charge would be harnessed for propulsion, as well as power to run a spacecraft’s systems. —Margherita Bassi, Smithsonian Magazine, 18 Apr. 2025

These short-period comets, with orbits lasting less than 20 years, were thought to deliver water with higher deuterium levels due to their formation in colder regions of the solar system. —Mark R. Weaver, Newsweek, 4 Dec. 2024

Brown dwarfs above 13 Jupiter masses can only fuse a hydrogen isotope called deuterium, providing a weak nuclear burn for a few million years. —Byadam Mann, science.org, 6 Nov. 2024

Muons displace electrons in the hydrogen atoms, resulting in hydrogen molecules made up of a deuterium and a tritium atom chemically bonded by a muon rather than an electron. —IEEE Spectrum, 3 Dec. 2024

Word History

Etymology

New Latin, from Greek deuteros second

First Known Use

1933, in the meaning defined above

Phrases Containing deuterium

• deuterium oxide

Rhymes for deuterium

• bacterium
• delirium
• imperium
• puerperium
• venereum
• agrobacterium
• corynebacterium
• mycobacterium
• cyanobacterium
• magisterium
• ministerium

Kids Definition

deuterium

noun

deu·​te·​ri·​um d(y)ü-ˈtir-ē-əm 

: the hydrogen isotope that is twice the mass of ordinary hydrogen

called also heavy hydrogen

Medical Definition

deuterium

noun

deu·​te·​ri·​um d(y)ü-ˈtir-ē-əm 

: an isotope of hydrogen that has one proton and one neutron in its nucleus and that has twice the mass of ordinary hydrogen

called also heavy hydrogen