cologarithm

[koh-law-guh-rith-uh m, -rith-uh m, -log-uh-]
noun Mathematics.
  1. the logarithm of the reciprocal of a number, often used in expressing the logarithm of a fraction: log 7/25 = log 7 + colog 25. Symbol: colog

Origin of cologarithm

First recorded in 1880–85; co- + logarithm
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for cologarithm

cologarithm

noun
  1. the logarithm of the reciprocal of a number; the negative value of the logarithmthe cologarithm of 4 is log 1/4 Abbreviation: colog
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