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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.

"It was amazing, I couldn't believe how many people were there at seven o'clock when we teed off," he said.

From BBC

"Because he said he would arrive at four o'clock in the afternoon. He arrived at seven o'clock, kept me standing there, practising curtsy and curtsy," she said.

From BBC

"By then it was probably three o'clock in the afternoon here, I called the Nobel Committee. Of course they were in bed, because it was probably one o'clock in the morning there," Dr Ramsell said.

From BBC

If the sun comes out - it's a two o'clock race, it was a four o'clock qualifying today - that makes quite a bit of difference.

From BBC

It's nine o'clock on a bitterly cold Monday evening and as temperatures dip below freezing, we are heading out with the Op Boss and Night Light police teams.

From BBC