Coordinated Universal Time (UTC)
zamân-e jahâni-ye hamrârâsté
Fr.: temps universel coordonné
An international high-precision time standard based on the Greenwich Mean Time and adjusted to compensate for divergence from atomic time. It is based on the non-uniform rotation of the Earth (UT1) and the perfectly uniform international atomic time (TAI). UTC differs from TAI by the total number of → leap seconds, so that UT1-UTC stays smaller than 0.9 sec in absolute value.