time-standard As a command 15 categories below time-standard Narrow by quantity 4 sidereal-time 4 act 1 activity 1 event 1 practice 1 solar-time 1 sidereal-time 4solar-time 1coordinated-universal-timedaylight-saving-timegeologic-time-scalegps-timeinternational-atomic-timejulian-dayleap-secondlocal-mean-timesidereal-daysidereal-hoursidereal-monthsidereal-yearunix-time