a radioactive isotope of hydrogen having an atomic weight of 3 and a half-life of c. 12.5 years: it decays by beta-particle emission and is used in thermonuclear bombs, thermonuclear fusion devices, as a radioactive tracer, etc.
Origin of tritiumModern Latin from Classical Greek tritos, third + -ium
A rare radioactive isotope of hydrogen, H-3, having one proton and two neutrons in the nucleus and a half-life of 12.3 years, prepared artificially for use as a tracer and as a constituent of hydrogen bombs.
Origin of tritiumFrom Greek tritos third ; see trei- in Indo-European roots.
From Ancient Greek τρίτος (tritos, “third”) + -ium.