protactinium
/ˌpɹəʊ.tækˈtɪn.i.əm/
pɹəʊ · TÆKTꞮN · i · əm (4 syllables)
English
Noun
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Definition
A chemical element (symbol Pa) with atomic number 91. A dense, silvery-gray actinide metal.
Etymology
From proto- + actinium.
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