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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of o'clock

First recorded in 1710–20; from o', a reduced form of of; see o' + clock 1 ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

"We had to stop at 10 o'clock in the morning."

From BBC ● Sep. 30, 2026

He’d go to bed probably at midnight, one o’clock, and he’s up taking the kids to school, he’s mountain biking, and he’s ready to roll.

From Los Angeles Times ● Aug. 13, 2026

“But we also like to deposit them back at their parents’ house at 7 o’clock, so we can be in bed to read at 8.”

From The Wall Street Journal ● Jul. 29, 2026

"You've got fans leaving at three o'clock in the morning or you're going the night before and having to pay for a hotel."

From BBC ● Jul. 24, 2026

By six o'clock the house was filled with delicious aromas.

From "Jeremy Thatcher, Dragon Hatcher" by Bruce Coville

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