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Greenwich, borough, Greater London, England

(Encyclopedia)Greenwich grĭnˈīj, grĕnˈ– [key], inner borough of Greater London, SE England, on the Thames River. ...

Greenwich, town, United States

(Encyclopedia)Greenwich grĕnˈĭch [key], residential town (2020 pop. 63,518), Fairfield co., SW Conn., on ...

ephemeris time

(Encyclopedia)ephemeris time (ET), astronomical time defined by the orbital motions of the earth, moon, and planets. The earth does not rotate with uniform speed, so the solar day is an imprecise unit of time. Ephe...

space-time

(Encyclopedia)space-time, central concept in the theory of relativity that replaces the earlier concepts of space and time as separate absolute entities. In relativity one cannot uniquely distinguish space and time...

sidereal time

(Encyclopedia)sidereal time (ST), time measured relative to the fixed stars; thus, the sidereal day is the period during which the earth completes one rotation on its axis so that some chosen star appears twice on ...

time zone

(Encyclopedia)time zone: see standard time.

time , sequential arrangement of all events

(Encyclopedia)time, sequential arrangement of all events, or the interval between two events in such a sequence. The concept of time may be discussed on several different levels: physical, psychological, philosophi...

time-division

(Encyclopedia)time-division: see multiplexing. ...

daylight saving time

(Encyclopedia)daylight saving time (DST), time observed when clocks and other timepieces are set ahead so that the sun will rise and set later in the day as measured by civil time. The amount of daylight on a given...

local solar time

(Encyclopedia)local solar time: see solar time. ...