Definitions

from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A radioactive rare-earth element prepared by fission of uranium or by neutron bombardment of neodymium, having nearly 50 isotopes and isomers, of which the most stable have half-lives of 2.62 years (Pm-147), 5.53 years (Pm-146), and 17.7 years (Pm-145). Promethium-147 is most easily obtained and is used as a source of beta rays. Atomic number 61; melting point 1,042°C; boiling point 3000°C; specific gravity 7.264 (25°C); valence 3. cross-reference: Periodic Table.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun a metallic chemical element (symbol Pm) with an atomic number of 61.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a soft silvery metallic element of the rare earth group having no stable isotope; was discovered in radioactive form as a fission product of uranium

Etymologies

from The American Heritage® Dictionary of the English Language, 4th Edition

[From Prometheus.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

1945. From the name of the Greek god Prometheus, who stole the fire from Mount Olympus and brought it down to mankind.

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Examples

  • It's live and it's all about promethium, element 61.

    A titan of an element Brian Clegg 2010

  • It's live and it's all about promethium, element 61.

    Archive 2010-03-01 Brian Clegg 2010

  • This uncertainty of just what Prometheus was responsible for is echoed in the uncertainty of who discovered the element promethium, number 61 in the periodic table.

    A titan of an element Brian Clegg 2010

  • This uncertainty of just what Prometheus was responsible for is echoed in the uncertainty of who discovered the element promethium, number 61 in the periodic table.

    Archive 2010-03-01 Brian Clegg 2010

  • But my dim-witted, testosterone blind buddies convinced me to take her off path” to get the underbelly coated with a mono-layer of promethium-deuterium-phosphate, otherwise known as PDP.

    365 tomorrows » 2006 » August : A New Free Flash Fiction SciFi Story Every Day 2006

  • A bomb made of promethium would never stop exploding, whatever that means, so I suppose a razor made of promethium would never dull.

    Week 6: Sent Forth from the Power Douglas Wolk 2006

  • For an issue in which chemical numbers are important it's odd that the razor company would be named after promethium, element 61, which is nasty, radioactive stuff.

    Archive 2006-06-01 Douglas Wolk 2006

  • For an issue in which chemical numbers are important it's odd that the razor company would be named after promethium, element 61, which is nasty, radioactive stuff.

    Week 6: Sent Forth from the Power Douglas Wolk 2006

  • For an issue in which chemical numbers are important it's odd that the razor company would be named after promethium, element 61, which is nasty, radioactive stuff.

    Week 6: Sent Forth from the Power Douglas Wolk 2006

  • So's part of the sea floor — for the promethium mining and lutigestoid mariculture projects.

    Perseus Spur May, Julian, 1931- 1998

Comments

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  • Pm.

    December 16, 2007