Definitions for "Isochronism"
Equal periods of time. A watch's ability to maintain its rate as the mainspring unwinds.
Occurring at equal intervals of time. The balance should not vary in its swing causing the watch to run any faster just after winding than it will a day later. From "Isos", meaning equal and "chronos", meaning time.
Keywords:  uniformity, time
uniformity in time
Keywords:  quality
The state or quality of being isochronous.