mercury arc

noun Electricity.

a bluish-green electric arc that has passed through a mercury-vapor cathode.


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Origin of mercury arc

First recorded in 1915–20 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for mercury arc

British Dictionary definitions for mercury arc

mercury arc


  1. an electric discharge through ionized mercury vapour, producing a brilliant bluish-green light containing ultraviolet radiation
  2. (as modifier)a mercury-arc rectifier See also ignitron
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