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Lewis base

noun Chemistry.
  1. any substance capable of forming a covalent bond with an acid by transferring a pair of electrons to it.

Origin of Lewis base

First recorded in 1960–65; named after G. N. Lewis
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for lewis base

Lewis base

noun
  1. a substance capable of donating a pair of electrons to an acid to form a covalent bondCompare Lewis acid

Word Origin for Lewis base

C20: named after G. N. Lewis (1875–1946), US chemist
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