[ 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.

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. 2019

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

Word Origin and History for dysprosium



element, obtained 1906 from an earth discovered in 1886, the last to be extracted from the complex earth called yttria, and named dysprosia in reference to the difficulty of obtaining it, from Greek dysprositos "hard to get at, difficult of access," from dys- "bad" (see dys-) + prositos "approachable." With metallic element suffix -ium.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine 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.

Science 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.