Simple Definition of plutonium

from our Learner's Dictionary

plutonium

noun

pluˈtoʊnijəm How to pronounce plutonium (audio)
: a radioactive element that is used to make nuclear energy and nuclear weapons

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“Plutonium.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/plutonium. Accessed 14 Apr. 2026.

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