tritium

noun

tri·​ti·​um ˈtri-tē-əm How to pronounce tritium (audio) ˈtri-shē- How to pronounce tritium (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But ramping up the production of tritium, which is usually produced from lithium, will prove far more difficult. Farhat Beg, The Conversation, 8 Jan. 2025 Oh yes, and there are also the usual slots – three, in this case – for optional vials of glow-in-the-dark tritium. Ben Coxworth, New Atlas, 16 Jan. 2025 This might entail surrounding the fusion reactor with lithium-containing material, which the reaction will convert into tritium. Farhat Beg, The Conversation, 8 Jan. 2025 This core component contains a gas such as deuterium and tritium that is encased in chemical explosives. Andrew Paul, Popular Science, 9 Jan. 2025 See all Example Sentences for tritium 

Word History

Etymology

New Latin, from Greek tritos third — more at third entry 1

First Known Use

1933, in the meaning defined above

Time Traveler
The first known use of tritium was in 1933

Dictionary Entries Near tritium

Cite this Entry

“Tritium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tritium. Accessed 25 Feb. 2025.

Kids Definition

tritium

noun
tri·​ti·​um ˈtrit-ē-əm How to pronounce tritium (audio) ˈtrish-ē- How to pronounce tritium (audio)
: 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 How to pronounce tritium (audio) ˈtrish-ē- How to pronounce tritium (audio)
: a radioactive isotope of hydrogen that has three times the mass of ordinary hydrogen
symbol T

More from Merriam-Webster on tritium

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