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{%type%} Definitions

WordNet 3.0Copyright Princeton University


Short "hint"

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

Usage examples (7)
  • Professor Meitner in 1918, and discovered protactinium, the long-lived mother substance of the actinium series.
  • Kudos to moose drool whose handle happens to rhyme with April Fools, too! for the initial protactinium outline.
  • Her expertise was on separating protactinium from carnotite and she had previously worked as a consultant for physicians and hospitals. 141
  • An element discovered in 1982 has been named meitnerium to honor Lise Meitner (1878-1968), the Austrian-Swedish physicist and mathematician who discovered the element... for more
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