plutonium

Plural: plutoniums

Noun

• a solid silvery grey radioactive transuranic element whose atoms can be split when bombarded with neutrons; found in minute quantities in uranium ores but is usually synthesized in nuclear reactors; 13 isotopes are known with the most important being plutonium 239
• The transuranic chemical element with atomic number 94 and symbol Pu: a silvery-gray fissile radioactive actinide metal that tarnishes when exposed to air.
• Alternative form of ploutonion.

Synonyms

atomic number 94, Pu

Related Words

Pluto, pluton, Plutonian, plutonic, plutonism