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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In the tokamak, scientists will heat up deuterium and tritium to 100 million degrees Celsius and fuse them together—producing heat that can be converted to electricity in the process.
—
Justin Worland, Time, 17 July 2025
Both use different approaches to achieve a promising form of nuclear fusion called magnetic confinement, which aims to ignite a fusion reaction in a plasma of the neutron-heavy hydrogen isotopes deuterium and tritium.
—Tom Metcalfe, Scientific American, 2 July 2025
Oh yes, and there's also the obligatory slot for an optional vial of glow-in-the-dark tritium.
—New Atlas, 19 June 2025
Low levels of tritium were found in ground water last year, and the latest monitoring showed that concentrations have declined along the western side of Unit 2.
—Teri Sforza, Oc Register, 11 June 2025
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Justin Worland, Time, 17 July 2025
Both use different approaches to achieve a promising form of nuclear fusion called magnetic confinement, which aims to ignite a fusion reaction in a plasma of the neutron-heavy hydrogen isotopes deuterium and tritium.
—Tom Metcalfe, Scientific American, 2 July 2025
Oh yes, and there's also the obligatory slot for an optional vial of glow-in-the-dark tritium.
—New Atlas, 19 June 2025
Low levels of tritium were found in ground water last year, and the latest monitoring showed that concentrations have declined along the western side of Unit 2.
—Teri Sforza, Oc Register, 11 June 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 29 Jul. 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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