tritium
noun
tri·ti·um
ˈtri-tē-əm 
ˈtri-shē-
ˈtri-shē-
: a radioactive isotope of hydrogen that has one proton and two neutrons in its nucleus and that has three times the mass of ordinary hydrogen
—symbol T
Examples of tritium in a Sentence
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From the early 1950s until the end of the Cold War, its primary mission was producing plutonium and tritium for the US nuclear weapons arsenal.
—
Aman Tripathi, Interesting Engineering, 3 Oct. 2025
Scientists have figured out how to collect helium-3 produced by the decay of tritium in nuclear weapons and power plants, but that yields less than 20 kg a year.
—Jeremy Bogaisky, Forbes.com, 2 Sep. 2025
These neutrons interact with the lithium to eventually produce tritium.
—New Atlas, 2 Sep. 2025
The Savannah River Site was built in 1951 as a means to produce material for nuclear weapons, primarily tritium and plutonium, to support America’s defense programs, according to the SRS website.
—Angel Saunders, People.com, 31 July 2025
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Aman Tripathi, Interesting Engineering, 3 Oct. 2025
Scientists have figured out how to collect helium-3 produced by the decay of tritium in nuclear weapons and power plants, but that yields less than 20 kg a year.
—Jeremy Bogaisky, Forbes.com, 2 Sep. 2025
These neutrons interact with the lithium to eventually produce tritium.
—New Atlas, 2 Sep. 2025
The Savannah River Site was built in 1951 as a means to produce material for nuclear weapons, primarily tritium and plutonium, to support America’s defense programs, according to the SRS website.
—Angel Saunders, People.com, 31 July 2025
See All Example Sentences for tritium
Cite this Entry
“Tritium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tritium. Accessed 30 Oct. 2025.
Copy CitationKids Definition
tritium
noun
tri·ti·um
ˈtrit-ē-əm
ˈtrish-ē-
ˈtrish-ē-
: a rare radioactive form of hydrogen having atoms with three times the mass of ordinary light hydrogen atoms
Medical Definition
tritium
noun
tri·ti·um
ˈtrit-ē-əm
ˈtrish-ē-
ˈtrish-ē-
: a radioactive isotope of hydrogen that has three times the mass of ordinary hydrogen
—symbol T
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