logarithm

noun

log·​a·​rithm ˈlȯ-gə-ˌri-t͟həm 

ˈlä-

: the exponent that indicates the power to which a base number is raised to produce a given number

the logarithm of 100 to the base 10 is 2

logarithmic

ˌlȯ-gə-ˈrit͟h-mik 

ˌlä-

adjective

logarithmically

ˌlȯ-gə-ˈrit͟h-mi-k(ə-)lē 

ˌlä-

adverb

Examples of logarithm in a Sentence

Recent Examples on the Web

The Quantum Threat Conventional cryptographic protocols such as RSA, ECC and Diffie-Hellman rely on the computational difficulty of mathematical problems like integer factorization and discrete logarithms to provide security. —Dino Dimarino, Forbes.com, 29 Apr. 2025

Recall that regressing the logarithm of bitcoin’s price against the logarithm of time generates a tight fit, and this is consistent with bitcoin's price following a power law. —Korok Ray, Forbes, 25 Feb. 2025

For cybersecurity, this means that quantum computers are closer to breaking traditional cryptographic methods like RSA and ECC, which rely on the computational infeasibility of factoring large numbers or solving discrete logarithms. —Abdo Riani, Forbes, 30 Dec. 2024

Given a set of possible characters in a message, Shannon’s formula defines the uncertainty about which character will appear next as the sum of the probability of each character appearing multiplied by the logarithm of that probability. —Zack Savitsky, Quanta Magazine, 13 Dec. 2024

Word History

Etymology

New Latin logarithmus, from log- + Greek arithmos number — more at arithmetic

First Known Use

circa 1616, in the meaning defined above

Phrases Containing logarithm

• common logarithm
• Napierian logarithm
• natural logarithm

Rhymes for logarithm

• algorithm
• rhythm

Kids Definition

logarithm

noun

log·​a·​rithm ˈlȯg-ə-ˌrit͟h-əm 

ˈläg-

: the exponent that indicates the power to which a base number is raised to produce a given number

the logarithm of 100 to the base 10 is 2

logarithmic

ˌlȯg-ə-ˈrit͟h-mik 

ˌläg-

adjective