deuterium

American  

[doo-teer-ee-uhm, dyoo-] / duˈtɪər i əm, dju- /

noun

Chemistry.

1. an isotope of hydrogen, having twice the mass of ordinary hydrogen; heavy hydrogen. 2 H, D; 2.01; 1.

---

deuterium British  

/ djuːˈtɪərɪəm /

noun

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

---

deuterium Scientific  

/ do̅o̅-tîr′ē-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.

2. Also called heavy hydrogen

3. See Note at heavy water

---

Etymology

Origin of deuterium

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

---

Compare meaning

How does deuterium compare to similar and commonly confused words? Explore the most common comparisons:

• deuterium vs. hydrogen

---

Example Sentences

See Examples For:

deuterium

"Neutrons are ideal at discerning light elements including hydrogen and its isotopes, such as deuterium."

From Science Daily ● Sep. 21, 2026

First-generation reactors will almost certainly be fueled by the hydrogen isotopes deuterium and tritium.

From The Wall Street Journal ● Dec. 28, 2025

In addition to spin polarizing half the fuels, the percentage of deuterium would be increased from the usual amount of roughly 60% or more.

From Science Daily ● Nov. 19, 2024

A good thing to note is that deuterium, a stable isotope of hydrogen, is much less expensive and can be found in seawater.

From Los Angeles Times ● Sep. 15, 2024

Tritium could be created by bombarding deuterium with copious neutrons in a heavy- water reactor.

From "Big Science" by Michael Hiltzik

Random Word

Spin the wheel and learn a new word!

---