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lanthanide

[lan-thuh-nahyd, -nid]
noun Chemistry.
  1. any element of the lanthanide series.

Origin of lanthanide

First recorded in 1925–30; lanthan(um) + -ide
Also called lan·tha·non [lan-thuh-non] /ˈlæn θəˌnɒn/.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for lanthanide

lanthanide

lanthanon (ˈlænθəˌnɒn)

noun
  1. any element of the lanthanide seriesAlso called: rare earth, rare-earth element

Word Origin for lanthanide

C19: from lanthanum + -ide
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
lanthanide in Medicine

lanthanide

[lăn′thə-nīd′]
n.
  1. Any of the chemically related elements with atomic numbers 57 through 71.rare earth rare-earth element
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
lanthanide in Science

lanthanide

[lăn′thə-nīd′]
  1. Any of a series of 15 naturally occurring metallic elements. The lanthanides include elements having atomic numbers 57 (lanthanum) through 71 (lutetium). They are grouped apart from the rest of the elements in the Periodic Table because they all behave in a similar way in chemical reactions. Also called rare-earth element See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.