Definition of tritium
: 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
Recent Examples of tritium from the Web
No, not robots fashioned of these materials or a new form of nuclear fusion that uses dried out husks and leaves to spark the deuterium-tritium cycle.
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Learn More about tritium
Britannica.com: Encyclopedia article about tritium
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