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tritium
noun
tri·ti·um
ˈtri-tē-əm
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
Radium continued to be used on military watches through the mid-20th century, and was finally phased out in favor of less dangerous tritium.
—Oren Hartov, Robb Report, 13 June 2024
These require heavy forms of hydrogen—deuterium and tritium—for the fusion stage of the device, which is triggered by a plutonium or uranium fission bomb.
—Siegfried S. Hecker, Foreign Affairs, 4 Dec. 2017
After that, four-digit Rolex dials use tritium luminescent paint, which typically loses its functionality after about 20 years.
—Allen Farmelo, Robb Report, 7 May 2024
Notes & Opinions on 4-Digit Rolexes Rolex switched from radium to tritium in 1963.
—Allen Farmelo, Robb Report, 7 May 2024
See all Example Sentences for tritium
These examples are programmatically compiled from various online sources to illustrate current usage of the word 'tritium.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
Word History
Etymology
New Latin, from Greek tritos third — more at third entry 1
First Known Use
1933, in the meaning defined above
Dictionary Entries Near tritium
Cite this Entry
“Tritium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tritium. Accessed 4 Jul. 2024.
Kids Definition
tritium
noun
tri·ti·um
ˈtrit-ē-əm
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-
: a radioactive isotope of hydrogen that has three times the mass of ordinary hydrogen
—symbol T
More from Merriam-Webster on tritium
Britannica.com: Encyclopedia article about tritium
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