Potentiometer
/pəˌtɛnʃɪˈɒmɪtə/noun
A three-terminal variable resistor used to divide voltage, and by extension any knob or slider working that way.
The Greek roots
Literally: “measure of potential”
The story of the word
A hybrid word, and a mismatched one: the first half is Latin potentia, power, and only the -meter is Greek. Nineteenth-century instrument makers built potentiometers to measure an unknown voltage by balancing it against a known one, with no current drawn at balance, which made them far more accurate than a moving-coil meter. Every volume knob and studio fader you have ever turned is the same idea reduced to a pot.
- How it travelled
- Latin and Ancient Greek → scientific coinage → English
- First recorded
- 19th century
The same roots elsewhere
Other languages reached for exactly the same Greek pieces.
Same family
In a sentence
Turn the potentiometer until the galvanometer reads zero.
The mixing desk has sixteen motorised potentiometers.