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voltaic couple

noun Electricity.
  1. a pair of substances, as two different metals, that when placed in a proper solution produces an electromotive force by chemical action.
Also called galvanic couple.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for voltaic couple

voltaic couple

noun
  1. physics a pair of dissimilar metals in an electrolyte with a potential difference between the metals resulting from chemical action
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