[ dis-proh-see-uh m, -shee- ]
/ dɪsˈproʊ si əm, -ʃi- /

noun Chemistry.

a rare-earth metallic element, highly reactive and paramagnetic, found in small amounts in various rare-earth minerals, as euxenite and monazite: used to absorb neutrons in nuclear reactors. Symbol: Dy; atomic weight: 162.50; atomic number: 66.


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Origin of dysprosium

1885–90; < New Latin < Greek dysprós(itos) hard to get at (dys- dys- + pros- to + itós, past participle of iénai to go) + -ium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for dysprosium

/ (dɪsˈprəʊsɪəm) /


a soft silvery-white metallic element of the lanthanide series: used in laser materials and as a neutron absorber in nuclear control rods. Symbol: Dy; atomic no: 66; atomic wt: 162.50; valency: 3; relative density: 8.551; melting pt: 1412°C; boiling pt: 2567°C

Word Origin for dysprosium

C20: New Latin, from Greek dusprositos difficult to get near + -ium
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for dysprosium

[ dĭs-prōzē-əm, -zhē-əm ]

n. Symbol Dy

A soft, silvery rare-earth element used in nuclear research. Atomic number 66.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Scientific definitions for dysprosium

[ dĭs-prōzē-əm ]


A soft, silvery metallic element of the lanthanide series. Because it has a high melting point and absorbs neutrons well, dysprosium is used to help control nuclear reactions. Atomic number 66; atomic weight 162.50; melting point 1,407°C; boiling point 2,600°C; specific gravity 8.536; valence 3. See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.