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

Another moment that I really like in the show is Odessa’s character, she wants to change a dinner reservation to five people at 8 o’clock.

From Los Angeles Times • Jun. 18, 2026

"When I was going home at 11 o'clock that night the bins were all full."

From BBC • May 27, 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

"I fail to understand why anybody... is serving people at five or six o’clock in the morning," he told the paper.

From Barron's • May 6, 2026

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

From "The Hidden Gallery" by Maryrose Wood