- any of the group of univalent metals including potassium, sodium, lithium, rubidium, cesium, and francium, whose hydroxides are alkalis.
Origin of alkali metal
First recorded in 1880–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- any of the monovalent metals lithium, sodium, potassium, rubidium, caesium, and francium, belonging to group 1A of the periodic table. They are all very reactive and electropositive
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 a group of soft, white, low-density, low-melting, highly reactive metallic elements, including lithium, sodium, potassium, rubidium, cesium, and francium.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- Any of a group of soft metallic elements that form alkali solutions when they combine with water. They include lithium, sodium, potassium, rubidium, cesium, and francium. Except for cesium, which has a gold sheen, alkali metals are white. The alkali metals have one electron in their outer shell, and therefore react easily with other elements and are found in nature only in compounds. See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.