# Definition of 'logarithm'

countable noun

In mathematics, the logarithm of a number is a number that it can be represented by in order to make a difficult multiplication or division sum simpler.

COBUILD Advanced English Dictionary. Copyright © HarperCollins Publishers

noun

the exponent indicating the power to which a fixed number, the base, must be raised to obtain a given number or variable. It is used esp to simplify multiplication and division: if ax = M, then the logarithm of M to the base a (written logaM) is x

. Often shortened to : log See also common logarithm, natural logarithmCollins English Dictionary. Copyright © HarperCollins Publishers

## Word origin of 'logarithm'

C17: from New Latin logarithmus, coined 1614 by John Napier, from Greek logos ratio, reckoning + arithmos number noun

Ancient Mathematics

the exponent expressing the power to which a fixed number (the base) must be raised in order to produce a given number (the antilogarithm): logarithms computed to the base 10 are often used for shortening mathematical calculations

Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.

## Derived forms

logarithmic (ˌlogaˈrithmic) adjective

logarithmically (ˌlogaˈrithmically)

adverb

## Word origin of 'logarithm'

ModL logarithmus < Gr logos, a word, proportion, ratio (see logic) + arithmos, number (see arithmetic)## Example sentences containing 'logarithm'

Times, Sunday Times (2011)

The notes on the keyboard get closer together according to the difference between the sequence of the logarithms of natural numbers.

Times, Sunday Times (2008) Times, Sunday Times (2008)It is easy to get lost in the figures and horrible memories of schoolday logarithms, but here is some context.

Times, Sunday Times (2015)## Trends of 'logarithm'

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## Source

Definition of

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