Wiktionary
n. (context music obsolete English) An interval of pitch equal to 1/1000 of a decade, practically identical to a heptameride.
Wikipedia
The savart is a unit of measurement for musical pitch intervals . One savart is equal to one thousandth of a decade ( 10/1: 3,986.313714 cents): 3.9863 cents. Today the savart has largely been replaced by the cent and the millioctave. The savart is practically the same as the earlier heptameride (eptameride), one seventh of a meride. One tenth of an heptameride is a decameride and a hundredth of an heptameride (thousandth of a decade) is a jot.
Usage examples of "savart".
Paris the French physicist Savart became acquainted with this phenomenon and devoted himself to its study.
Chladni and Savart together published a great number of these figures.