cologarithm: Meaning and Definition of

co•log•a•rithm

Pronunciation: (kō-lô'gu-ri"um, -rith"um, -log'u-), [key]
— n. Math.
  1. the logarithm of the reciprocal of a number, often used in expressing the logarithm of a fraction: log = log 7 + colog 25. Symbol: colog
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.