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{%type%} Definitions

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Short "hint"

n. - A short-lived radioactive metallic element formed from uranium and disintegrating eventually into lead.

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Usage examples (2)
  • Thus were found the mesothorium now used by physicians and manufactured industrially, radio-thorium, ionium, protoactinium, radio-lead, and other substances.
  • That's radioactive, but it takes two million years before it becomes protoactinium, which changes to uranium in twenty-seven days, which changes to thorium after a...
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