Number & MeasureGreek → English
Logarithm
/ˈlɔːɡərɪðəm/noun
The exponent to which a fixed base must be raised to produce a given number.
The Greek roots
λόγος
lógos
ratio, reckoning
ἀριθμός
arithmós
number
Literally: “ratio-number”
The story of the word
John Napier built the Latin logarithmus in 1614 and chose λόγος in its mathematical sense of ratio, not its everyday sense of word. The point was labour: his tables turned multiplication into addition, and Kepler used them to grind through the orbital calculations behind his third law. Napier spent about twenty years on the tables so that everyone after him would not have to.
- How it travelled
- Ancient Greek → Modern Latin → English
- First recorded
- 1610s
The same roots elsewhere
Other languages reached for exactly the same Greek pieces.
Same family
arithmeticlogicanalogycatalogue
In a sentence
Plot it on a logarithm scale and the curve straightens into a line.