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; o' + clock ¹ ( def. )

Example Sentences

"I get calls from seafarers at two o'clock, three o'clock in the morning. They call me the minute they have access to the internet," Arrachedi said on Wednesday by telephone from Spain.

From Barron's • Mar. 29, 2026

At seven o'clock on a Monday morning, a village paperboy is busily doing his rounds, his high-vis vest and yellow bag standing out against a grey blanket of fog.

From BBC • Mar. 16, 2026

What he likes at the 7 o’clock hand right now are dividend-paying stocks.

From MarketWatch • Jan. 27, 2026

"I really didn't like having a 12 o'clock curfew, because I just didn't feel like you should need it," he added.

From BBC • Jan. 13, 2026

Then Karly turned back to me and said, ‘Yeah. Eleven o’clock Saturday morning at the pool.’

From "Code Name Kingfisher" by Liz Kessler