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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; 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.

"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

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

At five o'clock we came to the checking station at Knik.

From Literature

It's now 24 years since Rhona Martin delivered the Stone of Destiny in Salt Lake City, watched by millions of rapt viewers at dark o'clock in the UK.

From BBC

Shepherd said the post-mortem examination finding a piece of apple in Kirsty's small bowel, which "fits very well indeed with Kirsty dying between three and four o'clock in the morning".

From BBC