The coordinate representing a global measure of time in a relativistic theory of gravity, most usually the general theory of relativity. This coordinate amounts to a universal way of labelling events. Each event has four coordinates: three in space and one in time. The coordinate time is useful because of its global definition, but it does not correspond to physical time. That will be different for different observers, who will measure their own proper time. Strictly, the coordinate time is not uniquely defined as it depends on the choice of coordinates. However, the term is used in practice to mean the time coordinate in a standard coordinate system.
Subjects: Astronomy and Astrophysics.