o'clock

American  

[uh-klok] / əˈklɒk /

adverb

1. of, by, or according to the clock (used in specifying the hour of the day).

   It is now 4 o'clock.

2. according to a method for indicating relative position whereby a plane in space is considered to be numbered as a clock's face, with 12 o'clock considered as directly ahead in horizontal position or straight up in vertical position.

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o'clock British  

/ əˈklɒk /

adverb

1. used after a number from one to twelve to indicate the hour of the day or night

2. used after a number to indicate direction or position relative to the observer, twelve o'clock being directly ahead or overhead and other positions being obtained by comparisons with a clock face

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Etymology

Origin of o'clock

First recorded in 1710–20; from o', a reduced form of of; see o' + clock ¹ ( def. )

Example Sentences

“I fail to understand why anybody in airport bars is serving people at five or six o’clock in the morning,” he told British newspaper the Times.

From The Wall Street Journal • Jun. 5, 2026

“But if I can just save it until 5, 6, or 8 o’clock at night, the prices are much higher so I make my money by doing that.”

From The Wall Street Journal • May 22, 2026

"We thought, 'Why don't we get married at 10 o'clock in the morning?' And then we had the celebrant service after."

From BBC • May 19, 2026

Then I said, “Oh, four o’clock — I gotta go.”

From Los Angeles Times • Apr. 30, 2026

Now it was nearly three o’clock, and another post was due any moment.

From "The Hidden Gallery" by Maryrose Wood