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

“To know that people are lining up as early as 5 o’clock in the morning, because it’s that important to them, tells me that the need is just so great,” said L.A.

From Los Angeles Times • May 14, 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

Only one, located at 9 o’clock and close to the nipple, slightly concerned Margolies, even though it hadn’t changed in size or shape.

From The Wall Street Journal • May 4, 2026

"The street was quiet, as you would expect, at three o'clock in the morning."

From BBC • May 2, 2026

I say at a little after two o’clock in the morning.

From "The Brightwood Code" by Monica Hesse