What does the "o" stand for in 9 o'clock?



Why do we use "o" in telling the time, e.g. 9 o'clock?

I looked it up in the dictionary but it did not say anything about the letter.


Used to specify the hour when telling the time.

  • ‘the gates will open at eight o'clock’

What does the "o" stand for?


Posted 2014-04-12T10:14:59.270


3In this case, the *o'* has a historical derivation, but speakers don't think of it as short for anything anymore. You can't replace it with of the. So this is a matter of etymology; it's not like "lots o' luck" where *o'* represents a reduced colloquial form of of. You'll have to learn o'clock as a single word. – snailplane – 2014-04-12T16:08:45.210



This website explains it quite nicely:

o'clock (adj.) c.1720, abbreviation of of the clock (1640s), from Middle English of the clokke (late 14c.).

The usage of o' as a shortened way to say of is not uncommon (this is called an apocopic form, when the last syllable or consonant is left unpronounced). Many o' these are relatively rare in written form, but you might see them when an author was trying to capture colloquial elocution in a quote:

  • "All I needed was the queen o' hearts for a straight flush!"
  • "Yer startin' your new job tomorrah, Jim? Well, best o' luck to ya!"

For some reason, o'clock is one exception where the o' became not only common, but formal.

"colloquial elocution" is a fancy way of saying "how people say words informally"


Posted 2014-04-12T10:14:59.270

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or "how folk really talk" – CoolHandLouis – 2014-04-12T13:35:43.803