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

“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

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

From BBC • May 27, 2026

"Now you're wearing this for the minute you walk in the door to the minute we leave the classroom at 3 o'clock."

From BBC • May 18, 2026

“If it’s not back before three o’clock at the latest, the rest of today’s Morpho event will be canceled.”

From "A Monster of a Mystery (The Hardy Boys: Secret Files, #5)" by Franklin W. Dixon