day and night

[day and night] or [night and day] {adv.} 1. For days without stopping; continually. Syn.: AROUND THE CLOCK.

Some filling stations on great highways are open day and night 365 days a year.

The three men took turns driving the truck, and they drove night and day for three days.

2. Every day and every evening.

The girl knitted day and night to finish the sweater before her mother's birthday.