protactinium
noun
prot·ac·tin·i·um
ˌprō-ˌtak-ˈti-nē-əm 
: a shiny radioactive metallic element of relatively short life see Chemical Elements Table
Examples of protactinium in a Sentence
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These natural uranium isotopes decay into the element thorium, which in turn decays into protactinium, and each has its own isotopes.
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Artemis Spyrou, The Conversation, 24 May 2022
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Artemis Spyrou, The Conversation, 24 May 2022
Cite this Entry
“Protactinium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protactinium. Accessed 3 Mar. 2025.
Copy CitationKids Definition
protactinium
noun
prot·ac·tin·i·um
ˌprōt-ˌak-ˈtin-ē-əm
: a shiny metallic radioactive element of short life see element
Medical Definition
protactinium
noun
prot·ac·tin·i·um
ˌprōt-ˌak-ˈtin-ē-əm
variants
also protoactinium
: a shiny metallic radioelement of relatively short life
—symbol Pa
see Chemical Elements Table
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