English
logarithm
Logarithm comes from New Latin logarithmus.
- New Latinc. 1500–1900logarithmus
- Englishtodaylogarithm
attested reconstructed ? uncertain or disputed
Lineage
- New Latinc. 1500–1900logarithmus
- Englishtodaylogarithm
A compound of λόγος ‘ratio, proportion’ + ἀριθμός ‘number’
Proto-Indo-European *leǵ- ‘to collect (words)’
Proto-Hellenic *lógos
Ancient Greek λόγος ‘ratio, proportion’
Proto-Indo-European *h₂rey- ‘to count, arrange’
Proto-Indo-European *h₂ri-dʰh₁-mó-s
Ancient Greek ἀριθμός ‘number’
The story
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.
Every English word from New Latin logarithmus
Today it means
noun 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.
Language periods are conventional ranges, not dates for this word.
Etymograph / New Latin logarithmus / logarithm