Muhurta
A unit of about 48 minutes, and the name for an auspicious window.
Classically the day from sunrise to sunset is divided into fifteen muhurtas, and the night into fifteen more, so a muhurta is roughly 48 minutes — but only roughly, because the divisions are of the real daylight and night lengths, which change through the year. The word is used two ways on this site: the unit itself, and the named windows built from it, such as Abhijit, Vijaya, Brahma and Godhuli. Named windows are computed from the day's actual sunrise and sunset for your location, never from a fixed clock time.