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logarithm Syllabification: log·a·rithm
Pronunciation: /ˈlôɡəˌriT͟Həm/
(abbreviation: log)

Definition of logarithm in English:


A quantity representing the power to which a fixed number (the base) must be raised to produce a given number.

Logarithms can be used to simplify calculations because the addition and subtraction of logarithms is equivalent to multiplication and division, although the use of printed tables of logarithms for this has declined with the spread of electronic calculators. They also allow a geometric relationship to be represented conveniently by a straight line. The base of a common logarithm is 10, and that of a natural logarithm is the number e (2.71828...)

Example sentences
  • We can use arithmetics with different bases, fractions, decimals, logarithms, powers, or simply words.
  • Other examples are negative numbers, complex numbers, trigonometry, raising to powers, logarithms, and the beginnings of calculus.
  • It was a 17th century Scottish baron, John Napier, who first discovered the power of the logarithm as an important function in mathematics.


Early 17th century: from modern Latin logarithmus, from Greek logos 'reckoning, ratio' + arithmos 'number'.

Words that rhyme with logarithm

algorithm • sempervivum

Definition of logarithm in:

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