• synonyms


noun, plural mhos. Electricity.
  1. See under siemens.
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Also called reciprocal ohm.


[see-muh nz]
noun (used with a singular verb)
  1. Electricity. the standard unit of electrical conductance in the International System of Units(SI), equal to the reciprocal of the ohm and replacing the equivalent MKS unit (mho). Abbreviation: S
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Origin of siemens

First recorded in 1930–35; named after Sir W. Siemens
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for mho

Historical Examples of mho

  • ROLF, mho brings up the rear, is about twenty, with an open face and stiffish butter-coloured hair.

    The Skin Game (Fourth Series Plays)

    John Galsworthy

  • As conductance is the reciprocal of resistance it is measured by the reciprocal ohm or mho.

    The Radio Amateur's Hand Book

    A. Frederick Collins

  • A conductor having a resistance of 100 ohms has a conductivity of .01 mho.

British Dictionary definitions for mho


noun plural mhos
  1. the former name for siemens
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Word Origin for mho

C19: formed by reversing the letters of ohm (first used by Lord Kelvin)


  1. Ernst Werner von (ɛrnst ˈvɛrnər fɔn). 1816–92, German engineer, inventor, and pioneer in telegraphy. Among his inventions are the self-excited dynamo and an electrolytic refining process
  2. his brother, Sir William, original name Karl Wilhelm Siemens. 1823–83, British engineer, born in Germany, who invented the open-hearth process for making steel
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noun plural siemens
  1. the derived SI unit of electrical conductance equal to 1 reciprocal ohmSymbol: S Formerly called: mho
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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

mho in Medicine


n. pl. mhos
  1. A siemens.
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n. pl. siemens
  1. A unit of electrical conductance in the International System of Units, equal to one ampere per volt.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

mho in Science


  1. The SI derived unit of electrical conductance, equal to one ampere per volt. It is equivalent to the reciprocal of the ohm unit. Also called siemens
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Plural siemens
  1. See mho.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.