# Meaning of once and while in "once in a while"

How did "once in a while" come to mean "occasionally, from time to time"?

I understand it is an idiomatic usage, but "once" means "one time" and "while" means "in the meantime" , so how can the expression be used to refer to a number of different times?

Has "once" or "while" also other, possibly archaic, meanings? I could not find any in online dictionaries.

• Don't forget that 'while' also has the meaning of a period or stretch of time (albeit a rather short one in most cases) as in: "it took him a while to get there" Commented Feb 13, 2016 at 17:04
• I am not sure, I think that "once in a while" suggests a number (though small) of possible occurrences in the future, while "once in a blue moon" suggests a much rarer occurrence. Commented Feb 13, 2016 at 17:07
• I deleted my comment since it was pretty much what dukerasputin said. However, I didn't mean "once in a while", "once in a lifetime" and "once in a blue moon" mean the same thing, but only that the structure is the same. I was trying to illustrate the idea that "while" is a noun just like "lifetime" or "blue moon" are.
– Yay
Commented Feb 13, 2016 at 17:17

I think "once in a while" is parallel to expressions like "once a day," "once in every two months" that also refer to periodic events. The expression after "once" tells us how long it is between the different times; the action is done "once" for each of these time periods, but multiple times overall. I know people have made this point in other answers and comments, but maybe rephrasing it this way can help a bit.

"While" does not just mean "in the meantime." The first definition of while in the Oxford English Dictionary is

A portion of time, considered with respect to its duration; = time n. 1, 2, rarely 4 or 6. Now almost exclusively in certain connections (see below), the ordinary word being time.

We can see a similar use in expressions like "I'll be gone for a while" = "I'll be gone for a time period of indefinite but significant length."

• This. I'm surprised there are any other interpretations. "Once in a while" means once in a sizable time period but more frequent than once in a lifetime. Teasing out sizable time period: at least long enough for the main effect of the event happening to wear off, not frequent, possibly habitual but not on set schedule (if acted by the speaker) or with an element of randomness and surprise if acted upon the speaker ("Once in a while I get headaches.").
– A.S.
Commented Feb 29, 2016 at 3:51
• This is the most accurate and straightforward answer to the question asked. Commented Feb 29, 2016 at 13:42

It means one time (at least) in a set of times or a period of time (a while).

A while is an indefinite period of time. If the condition holds at even one moment during that period then the condition holds for once in a while.

Update (as suggested by @Cerberos) from comments I wrote here:

"Where is it said that once means 'at least one time'?"

"Once" means one time. I added "(at least)" gratuitously. Consider it removed, if you like. The phrase "Once in a while" means one time in an arbitrary (indefinite, nonspecific) time period. As such, it has come to mean repeatedly one such time in one such arbitrary period, that is, multiple arbitrary occurrences in multiple arbitrary time periods. Since the periods are arbitrary, it means, in effect, at least one time in an arbitrary period. If it occurs once in time period A and once in time period B then it occurs twice in the union of A and B, which is another arbitrary time period.

"yours is a comment rather than a real answer."

Fair enough. But you seem to think that "once in a while" is an idiom, and you wonder about how the idiom evolved. My answer is that a literal reading of once in an arbitrary while suffices. No real evolution ("come to mean") or "idiomatic usage" needed as a hypothesis. Same thing with "once upon a time", although we don't use "upon" here nowadays, so that is idiomatic now.

"I don't think the meaning is actually literal as Drew suggests. It should mean "one time in a period of time" not "from time to time"."

Actually, I did not suggest that the meaning can only be literal, i.e., that a literal meaning is necessary. I said that a literal meaning suffices - it can be read literally, and the meaning in that case is what one would expect. And a reading of "from time to time" follows from a literal meaning of "one time in a period of time" (because...because...time).

I tried to show how the meaning you understand is related logically to a literal meaning. That relation is as much of an "evolution" as I can come up with, I'm afraid. It doesn't pretend to be a real, historical evolution but is a logical becoming (relation between concepts). Then again, history can sometimes be underpinned by logic... ;-)

• Can you please support you answer with some evidence, it sounds just like your personal opinion. Where is it said that once means "at least one time"? Commented Feb 13, 2016 at 19:53
• Once means one time. I added "(at least)" gratuitously. Consider it removed, if you like. The phrase "Once in a while" means one time in an arbitrary (indefinite, nonspecific) time period. As such, it has come to mean repeatedly one such time in one such arbitrary period, that is, multiple arbitrary occurrences in multiple arbitrary time periods. Since the periods are arbitrary, it means, in effect, at least one time in an arbitrary period. If it occurs once in time period A and once in time period B then it occurs twice in the union of A and B, which is another arbitrary time period.
– Drew
Commented Feb 13, 2016 at 20:27
• There might be evidence, but I don't have any and won't be looking any up.
– Drew
Commented Feb 13, 2016 at 21:13
• Ok, that to me means that yours is a comment rather than a real answer. Thanks for your help. Commented Feb 13, 2016 at 21:28
• Fair enough. But you seem to think that once in a while is an idiom, and you wonder about how the idiom evolved. My answer is that a literal reading of once in an arbitrary while suffices. No real evolution ("come to mean") or "idiomatic usage" needed as a hypothesis. Same thing with "once upon a time", although we don't use "upon" here nowadays, so that is idiomatic now.
– Drew
Commented Feb 13, 2016 at 23:41

It's fairly straight forward.

In a literal interpretation it means that in a unspecific, but generally long period of time, this event will occur once.

It would be similar to saying:

Once in a hundred years the Oodjy Boodjy plant will bloom.

In practice there's an implication of variance on both the frequency and period of the event.

When we say 'once in a while' we're emphasising that

1. The event does occur regularly
2. But the event does not occur often.

The length of the period is determined by the context.

For example if an astrophysicist said

Once in a while a comet will crash into a planet creating a large explosion.

he's probably talking about a period of hundreds of thousands, or millions of years.

Whereas if a biologist observing ants said

Once in a while one of them will run off course.

he's likely to be talking about a period of minutes.

• Would you really use "once in a while" to refer to a period of minutes? To me, once in a while is at least a few times in a lifetime (but usually more often than that) e.g "once in a while your life will dramatically change" but definitely rarer than once every ~20-30 characteristic time-lengths. I'd use "every once in a while" in the ant example to refer to period of minutes and reserve "once in a while" to at least 5 minutes or so since running of course is not an instantaneous process. Just trying to roughly quantify expression in relation to characteristic time-scale.
– A.S.
Commented Feb 29, 2016 at 5:04

"once in a while" doesn't really mean "occasionally, from time to time". That is the literal meaning, of course, but it misses the point of the usage.

"Once in a while" is an evasion. It is a way of deliberately not answering the question "how often"?

`````` How often do you bet on the game?

Once in a while.
``````

This usage does not deny that the person bets, but give no information about the frequency with which they do so. It is a way of answering without answering, a way of saying "I'm not going to tell you." without being rude.

Another example is "every now and then". Consider what the literal meaning of that phrase might be. What does "every now" mean or "every then"?

These are related to other non-answers, like "a little bit" or "from time to time".

The questions, therefore, is not how they came to mean something, but how they came to mean nothing.

• I disagree that "occasionally, from time to time" is the literal meaning of "once in a while", although some speakers may well use it to avoid giving a definitive answer.
– Egox
Commented Feb 27, 2016 at 12:55
• Evasion is only one of many possible reasons to employ "once in a while." For instance, in the Grateful Dead's "Scarlet Begonias," > Once in a while > you get shown the light > in the strangest of places > if you look at it right specifies no particular frequency, and for good reason: it's different for everybody! Commented Feb 28, 2016 at 18:56
• You must feel physical pain whenever you see error bars.
– A.S.
Commented Feb 29, 2016 at 4:16