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
Recent Examples on the Web
On Earth, scientists are aiming to fuse deuterium and tritium—both isotopes, or versions, of hydrogen.
—
Margherita Bassi, Smithsonian Magazine, 18 Apr. 2025
The papers detail the structural design, the behavior of the plasma within it, handling of the helium produced by fusion, generation of tritium from the neutrons produced, and obtaining heat from the whole thing.
—ArsTechnica, 1 Apr. 2025
Buyers who go for this option can choose between glowing plastic tubes that need to be recharged by exposure to bright light, or vials of slightly radioactive(!) tritium, which doesn't require charging.
—Ben Coxworth, New Atlas, 24 Mar. 2025
Unlike nuclear fission – which splits atoms and creates dangerous radioactive waste – fusion uses hydrogen isotopes (like tritium and deuterium) and produces helium as a harmless byproduct.
—New Atlas, 22 Dec. 2024
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Margherita Bassi, Smithsonian Magazine, 18 Apr. 2025
The papers detail the structural design, the behavior of the plasma within it, handling of the helium produced by fusion, generation of tritium from the neutrons produced, and obtaining heat from the whole thing.
—ArsTechnica, 1 Apr. 2025
Buyers who go for this option can choose between glowing plastic tubes that need to be recharged by exposure to bright light, or vials of slightly radioactive(!) tritium, which doesn't require charging.
—Ben Coxworth, New Atlas, 24 Mar. 2025
Unlike nuclear fission – which splits atoms and creates dangerous radioactive waste – fusion uses hydrogen isotopes (like tritium and deuterium) and produces helium as a harmless byproduct.
—New Atlas, 22 Dec. 2024
See All Example Sentences for tritium
Cite this Entry
“Tritium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tritium. Accessed 24 Apr. 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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