on the hour

"On the half hour I get five minutes to stand at attention."

It was exactly on the hour, four in the morning.

The call was sent on the hour by my friend.

I don't think really well on two hours of sleep.

It goes on 24 hours a day, seven days a week.

This can go on between four and eight hours each day.

But she said moving to a system based on 24 hours instead of 18 was sound.

At home, they leave their television on 24 hours a day.

When he cut back on his hours, the parents started having more trouble.

But now he would have the opportunity to focus on her for hours.