Astronomers measured the planet's rotation over several sidereal days to determine its axial tilt.

We’ve planned three M-days this quarter to complete the system updates.

During the summer, we spent many stellar days stargazing along the coast.

The days after the accident were the hardest to remember.

Workers are entitled to several days of rest each year to recover their energy.

Many ancient texts warn of the days of judgement that will test the hearts of humanity.

After each market day, the stalls left behind days' residues that the staff cleared away.

Because of the storm, garbage days this week were moved to Friday and Sunday.

The village elders observed the Sabbath-days with quiet prayers and simple meals.

During the Victory Days, people gathered in the square to celebrate the end of the long conflict.