Coasting mode

Coasting mode: In timing-dependent systems, a free-running operational timing mode in which continuous or periodic measurement of clock error, i.e., of timing error, is not made.

Note: Operation in the coasting mode may be enhanced for a period of time by using clock-error data or clock-correction data (obtained during a prior period of operation in the tracking mode) to estimate clock corrections.

Source: from Federal Standard 1037C