- any element in any of the series of elements with atomic numbers 21–29, 39–47, 57–79, and 89–107, that in a given inner orbital has less than a full quota of electrons.
Origin of transition element
First recorded in 1920–25
Also called transition metal.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- chem any element belonging to one of three series of elements with atomic numbers between 21 and 30, 39 and 48, and 57 and 80. They have an incomplete penultimate electron shell and tend to exhibit more than one valency and to form complexes
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
- Any of the metallic elements within Groups 3 through 12 in the Periodic Table that have an incomplete inner electron shell and that serve as transitional links between the most and the least electropositive in a series of elements. They are characterized by multiple valences, colored compounds, and the ability to form stable complex ions. See Periodic Table. See Note at metal.
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