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

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

From BBC • May 27, 2026

PETALUMA, Calif.—Whiskers are spreading across American politics like a five o’clock shadow.

From The Wall Street Journal • 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

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

From Los Angeles Times • Apr. 30, 2026

“Yep. I’m going to bring water somehow. And head out at seven o’clock at the latest, I think. So this doesn’t happen again.”

From "Keeping Pace" by Laurie Morrison