(Christianity) the hour of fasting and prayer before communion is to be taken. / (Ireland, informal) the hour between 2.30 pm and 3.30 pm that pubs formerly had to shut to comply with licencing laws.

Happening hourly, but at 30 minutes past each hour; ie, 08:30, 09:30 etc. / Happening on the hour and at 30 minutes after the hour. / (soccer) At thirty minutes into a half.

(temporal location, idiomatic) Late into the night or early morning; when people ought to be sleeping.

The very early morning; the early morning hours; the nighttime hours following midnight, when most people are asleep.

(idiomatic) The time at (or very close to) the start of the next hour of time.

Alternative spelling of bankers' hours

The time period between 10 a.m. and 3 p.m. of a day. / (figuratively) Any easy job, especially one with a short working day.

Rush hour. / (attributive, often hyphenated) Relating to peak periods in traffic and transportation.

The period of twilight when the Sun is approximately 4-8° below the horizon and the sky is within a range of blue colors.

plural of blue hour