logarithm
UK /ˈlɒɡ.ə.ɹɪ.ð(ə)m/ · US /ˈlɑ.ɡə.ɹɪ.ð(ə)m/ noun
Forms logarithms
- noun (mathematics) For a number x, the exponent by which a given base number must be raised in order to obtain the power x. Written log _bx. For example, log ₁₀1000=3 because 10³=1000 and log ₂16=4 because 2⁴=16.
Synonyms
Etymology
From New Latin logarithmus, coined by Scottish mathematician John Napier from Ancient Greek λόγος (lógos, “ratio, proportion”) and ἀριθμός (arithmós, “number”). Napier set a geometric progression (a sequence of equal ratios) against an arithmetic progression (a sequence of equal differences), so that the logarithm of a number counts the ratios separating it from a starting value, turning multiplication into addition.
Webster’s 1913
- noun One of a class of auxiliary numbers, devised by John Napier, of Merchiston, Scotland (1550-1617), to abridge arithmetical calculations, by the use of addition and subtraction in place of multiplication and division.
Etymology [Gr. logarithme.]
Sources: Wiktionary · Webster’s 1913 — from the Wiktionary entry “logarithm”, CC BY-SA 4.0. Details