24 hour clock

I always liked the expression, “oh-dark-thirty,” which I presume means it’s about time for the bar to close.

Seventeen could be 12:17 am a.k.a. 0017.

What’s does that expression mean? On a non-24-hour clock, I can see how “3 dark” might mean 3am rather than 3pm. But the ambiguity isn’t there on a 24-hour clock for 0030 hours.

I found one place claiming that it doesn’t mean 0030 specifically, it’s just a humorous military expression for a nonspecific ungodly hour of the night when you’d rather not be awake, is that correct?

Fahhhhhhhhhhhhhhkkkkkk!

You East-coasters got it weird.

While I’ve not served in the military, that’s exactly what I’ve always understood the expression to mean – though, in how I’ve heard it used, also seems to refer to having to wake up, or be someplace, way too early in the morning.

If someone said it’s 17 I would respond 17 what. if they said seventeen hundred I would know it is 5:00 PM. And it is written 1700 not 17:00

It just means it is ungodly early because it is still dark out.

All my clocks are set to 24h time but I think and say “5pm” when I read 1700.

No, that’s not how it works. That’s Zero Seventeen. Nobody would possibly think such a thing unless they’re just trying to spur debate.

I believe so. As Ramira’s experience confirms, it seems that it is perfectly normal for the English speaking international community, especially in mainland Europe, to simply drop the “hundred”. As a member of the military, I (we) do it all the time. It’s just easier and faster to say, and it’s understood completely. But, before answering the questions which called for nonmilitary usage, I tried to think about conversations with nonmilitary people. I’ve never known any nonmilitary people in the US who use the 24 hour clock. So, my only experience with nonmilitary, English conversations about time using the 24 hour clock occur elsewhere. When thinking about English language interactions with people in countries that use the 24 Hour clock, I seem to recall that they don’t often say the “hundred” either. It’s not something I really paid attention to before this thread, but I am positive that, when speaking English, people either say hundred or just the number. And, it’s never confusing or ambiguous.

I can’t say for sure about England, I’ve only visited once. But I know that in the US, I’d get a puzzled look if I said any number higher than 12, regardless of what followed.

Oh-dark-thirty is simply a humorous expression. It is just means, really early, before the sun comes up. See also: Ass Crack of Dawn

If you asked me what time it was. And I answered “17”. And you followed up with “Seventeen What”. I’d say, “Seventeen Exactly”. Or, depending on how slow you were to respond, I might say, “It’s Seventeen oh one”. I don’t I’d say “hundred”. That would be rude. Like if someone said it was “Five”, and after being asked “Five what?” they say, “Five o’clock”. That’s rude. If someone says “Five What” or “Seventeen What”, usually they want to know a more accurate time. They think it might be 5 or 10 minutes after the hour and they need to know exactly.

After thinking about this, I’ll agree that for the first nine minutes after mid-night, there could possibly be confusion. Though, in practice, it would be next to impossible to confuse such a thing. If someone said, “We’re going to wake up at Zero Two and start getting ready to go.” Nobody would think that means “0002 Hours / 12:02 a.m.” Similarly, if someone were asking for the time, and it was 12:02 a.m, the response would probably be “Just passed midnight”. So, context plays a role there, I guess.

I think that’s the best interpretation.

It could be that you dropped the hours indicator, or it could be that you dropped the hours value and are referring to minutes.

In either case, the sender of the communication makes a choice based on perceived shared context with the receiver.
To claim that the assumed shared context is always accurate (i.e. comm is unambiguous) is not really a defendable position.

Raises hand.

Computer programmers use the 24 hour clock. I had to get accustomed to it after entering the field.

I say 17 or Oh 8 for morning.

I was struggling to learn it until my supervisor (ex military) told me to subtract 12. 17, that’s 5.

Sure, but it seems like people are forgetting that we do this with the 12-hour clock all the time. Two O’Clock A.M. becomes simply two. Not a single person anywhere would think it’s the hour being dropped in favor of just giving the minutes. To suggest this is ridiculous. If it’s exactly 1700, then saying seventeen is sufficient and unambiguous. If it’s a quarter after that, then of course one would say 1715.

I mean, seriously, if the person’s answer to “What time is it?” was “Five” instead of “Seventeen”, would you think the he was referring to minutes? Would Five have made you wonder if it was currently morning or early evening? You should know that it’s at least passed midday, so “five” should be enough of an answer to tell you that it is currently Five O’Clock p.m. Similarly, 17 is enough to tell you that it is currently Seventeen Hundred Hours. If it’s not exactly Five, then “Five Oh Eight” would tell you it’s 5:08 p.m. Similarly, “Seventeen Oh Eight” would work. Nobody just says the minutes. I don’t understand why you’d say that it could be that the hours indicator was dropped.

This ^. If I asked the time and was told “It’s 3”, I wouldn’t ask “3 minutes after what?” Even as someone who rarely thinks about 24 hour time, but knows how to convert it to am/pm time, an answer of “17” might make me pause a minute, but I think I’d catch on.

People almost always specify “X-hundred,” and it is mandatory when communicating by radio. When speaking informally, you will still hear people say things like, “I’ve been up since three” where it is understood from context that they mean three in the morning.

FWIW, the military system isn’t foolproof. I was once downrange on a camp where the conventional forces used local time but the SF guys used Zulu time. Hilarity ensued.

That’s how it’s done in Israel: it’s written as a 24-hour clock, but usually pronounced as a 12-hour clock, so you’ג write “17:00” and say “Five” or “Five in the evening”. If you’re being precise - like when you’re dictating a list of times - then you’d say “Seventeen zero zero”.

I can. Happy to help.

Using the 24 hour clock in normal conversation isn’t standard, unless we’re referring to something which is typically quoted in such… say, train times. In which case we’d say the ‘hundred’ bit.

‘Which train are we getting to London?’
‘The thirteen hundred’.

As for the BBC World Service, I’d love to hear a link to an example, because I’m finding it hard to believe at the moment.

Civilians (other than aviators and ham radio types) don’t generally use the 24-hour system in my neck of the woods (South Africa). And when we do, it’s with the “oh-X-hundred hours” formulation.

If I was asked by someone when we were meeting and I answered “seventeen”, they’d probably look at me like I’d just grown a third head.