day of sicknessmeans, in general, any calendar day, including days that would normally be rest days, on which an employee is not able to work because of any physical or mental illness or injury.
period of continuing sicknessrefers to a period of time when an employee is not able to work on account of illness, injury, sickness or disease, including inability caused by pregnancy, miscarriage or childbirth.
registration periodmeans, with respect to any employee, the period which begins with the first day with respect to which a statement of sickness for a period of continuing sickness is filed in his or her behalf in accordance with this part, or the first such day after the end of a registration period which will have begun with a day with respect to which a statement of sickness for a period of continuing sickness was filed in his or her behalf, and ends with whichever is the earlier of: