Fact Checked

What Does "in a Flash" Mean?

Jim B.
Jim B.

"In a flash" is an English idiom that refers to something that happens in an instant or in a very fast nature. This can refer to something that happens instantaneously or something that will only take a short amount of time from the time when the phrase is spoken. Another way to use "in a flash" is as a means of conveying that something, like an idea, has come upon someone in a very sudden fashion. The phrase gets its meaning from the way that a flash of lightning appears in an instant without any warning.

It is common for people speaking English to use words or short phrases which have accepted meanings that are far different from what one might expect from the literal definitions of the words they contain. These words and phrases are known as idioms, which can be extremely useful in allowing speakers to sound more colloquial and colorful with their conversations. Idioms get their meanings not from their literal definitions or even from the way they were first used but rather from the way they are used in a culture. One idiom that denotes a sudden action is the phrase "in a flash."

A flash of lightning.
A flash of lightning.

If something is described in this manner, it means that it will occur or has already occurred in a very brief window of time. There is usually some amount of exaggeration involved, but listeners familiar with the idiom can distinguish this and understand the intent of the speaker. As an example of how this phrase is used, consider the sentence, "I know you're worried about me going, but I'll be back in a flash."

There are also occasions when this phrase is used to describe a thought or idea which appears in someone's brain very quickly out of nowhere. It is often used to describe someone who has been searching in vain for some sort of inspiration until it quickly arrives. For example, someone might say, "I was stuck on the answer to that test for an hour but then it came to me in a flash."

The meaning of this phrase comes from the manner in which lightning strikes. Lightning provides a flash of light which illuminates a dark sky for a brief moment before disappearing just as quickly. As a result, it provides a good basis for this idiomatic expression. "In a flash" is not to be taken literally, but the figurative allusion to speed is quite clear.

You might also Like

Discussion Comments

@cloudel – Those multiplication flash cards always intimidated me. I hated having things presented quickly, because it made me nervous and put me under pressure.

So, the term “in a flash” does not conjure up images of cards in my mind. Instead, I think of beautiful lightning. We get a lot of intense thunderstorms around here, especially during the summer, and they produce gorgeous streaks of purple and pink flashes.

I have seen lightning strike an object close by before, and though it was a bit terrifying, it was also beautiful. A huge pink flash filled the air, followed quickly by a loud boom. The quicker that thunder sounds after you see a strike, the closer you know it is to you, so if it sounds “in a flash,” you know to seek shelter.

The phrase “in a flash” always makes me think of those math flash cards that our teachers used back in elementary school. My parents had tried to teach me the basics of math before I started learning it at school, but I could never get it -- I guess you could say that the flash cards helped me learn in a flash!

It seems that if I repeat things enough times to my dog over a period of months, she catches on to their meaning. I recently started telling her that I would be back in a flash, and now, she knows to anticipate my quick return.

I work from home, but I go to a friend's house for lunch every day. I always tell my dog, “I'll be back in a flash.” She always perks her ears up when I say this, and she sits down where I usually park my car. When I get back, she is waiting expectantly.

When I don't tell her that I'll be back in a flash, she usually goes to her favorite cool spot in the back yard and lies down for a nap. I think it's so neat that even she can catch onto idioms!


@andee – I do some of my best thinking in the shower, too. I have also had things come to me in a flash while I was mowing the lawn. I think that the dull task of riding up and down rows of grass relaxed my brain enough so that the revelation could get through.

I write songs, and sometimes, I get stuck at certain points. This frustrates me, because I know that the song could be awesome if I just had one more line that rhymed and fit the theme.

More often than not, the lyric will come to me in a flash. Trying to rack my brain for it usually produces no results. I have to rely on sudden inspiration.


The first time my three year old grandson heard me say, "I'll be back in a flash," he didn't understand what I meant! It can be hard trying to explain an idiom to a young person.

I tried to explain it to him the best I could, but I don't think he fully understood what I meant. He has heard me use that expression several times since then, and as he has gotten older, it is easier for him to understand what I mean.

Some idioms are easier to understand than others. Comparing this to a flash of lightening is a good way to try and explain it, as that is something they can easily relate to.

Many times when I am taking a shower is when an idea or solution to a problem will come to me in a flash. It's almost like when my mind stops focusing on it so intently, then it will suddenly pop in my head just like a flash of lightening.

I often find myself wondering why I didn't think of that sooner. I don't know why this works the way it does, but I have been very thankful it does.

Most of the time this is the perfect answer for what I have been trying to come up with, and to have it just flash through my mind like that is inspiring.

Post your comments
Forgot password?
    • A flash of lightning.
      By: Leonid
      A flash of lightning.