We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What are the Origins of the Phrase "Let the Cat out of the Bag"?

Mary McMahon
Updated May 23, 2024
Our promise to you
Language & Humanities is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At Language & Humanities, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Many people use the phrase “let the cat out of the bag” to refer to divulging a secret, but they are often unaware of the colorful history behind the term. As is the case with many idioms, the origins of the phrase are actually rather interesting, and they provide an intriguing insight into the lives of historical people. Delving into the origins of such terms can sometimes lead the researcher along fascinating tangents, as well.

In order to understand the origins of "let the cat out of the bag," it helps to understand how medieval markets worked. During the Middle Ages, markets or fairs were held to sell livestock, produce, and other goods from around a region. Most of the livestock was sold alive, usually in sacks so that the purchaser could bring it home relatively neatly. As a general rule, someone would inspect the pigs, chickens, and so forth for sale and pick one out, and then the farmer would bag the animal so that it could be carried.

Unscrupulous merchants might replace the livestock with a cat, since cats were readily available. The unknowing customer would carry the bag home, open it, and realize that he or she had been swindled. However, the plot relied on not letting the cat out of the bag too early. If the bag was opened in the marketplace, the customer could demand reparations from the merchant, since the secret would be out. Of course, the scheme would also rely on a quiet cat, since most people know the difference between an oink and a meow.

Some people have claimed that the term is related to the cat-o-nine tails famously used in naval discipline. However, this link seems tenuous at best, since there is no clear connection between letting the cat out of the bag and nautical punishments. Removing a whip from a bag is clearly not a euphemism for revealing a secret or spoiling a scam.

Incidentally, this practice is also related to the common term “pig in a poke.” A “poke” is a bag in some dialects, and a pig in a poke is, therefore, a pig in a bag or sack. The full idiom is usually “don't buy a pig in a poke,” meaning that buyers should inspect goods before purchasing them and taking them home. Otherwise, they may let the cat out of the bag too late, resulting in a rather large disappointment.

Language & Humanities is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Mary McMahon
By Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a Language & Humanities researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.

Discussion Comments
By anon995151 — On Apr 07, 2016

Interesting to see the level of diverse opinions about this.

I have read some old stories that cause me to believe that the correct answer is to do with the drowning of cats.

Yes indeed, putting kittens into a bag and drowning them was a very common and widespread practice for dealing with cat overpopulation. It also can be traumatic for children. Letting the cat out of the bag means that you have to deal with the consequences of having of take care of the cats.

Similarly, if you let a secret out of the bag e.g. reveal it. then you will have to deal with the consequences which result from that revelation. "He let the cat out of the bag" (revealed the secret) and now we have to deal with the consequences.

"Pig in a poke" certainly does refer to markets as this article states, but it is implausible that someone would try to pull a fast one, by putting a cat into a bag instead. There is a huge difference in both weight and shape. Nobody would be fooled by the substitution. It doesn't pass the smell test.

By anon265019 — On Apr 30, 2012

I agree with anon77124.

The nautical reference was that once the cat-o-nine tails was removed from the bag the discipline could not be stopped or undone. "There is no going back" to put it another way. Similarly, once a secret or scam is revealed, there is no undoing of the revelation.

A sailor trying to avoid punishment may be told, "Too late. The cat's out of the bag."

By anon260022 — On Apr 09, 2012

It's obviously a reference to drowning cats.

By anon142907 — On Jan 14, 2011

Please add to the prior post about the beaten cat in the bag, that I am referring to a Medieval practice in the British Isles.

By anon142905 — On Jan 14, 2011

"Letting the cat out of the bag" could mean letting a live, very angry and beaten cat out of the bag, before it had been beaten to death. In Medieval times there were festivals where one of the activities was that men would take turns swinging sticks at a suspended bag with a cat inside of it. Reference: "Stations of the Sun" published by the Oxford Press.

The Christians (and probably many other people) didn't like this practice and tried to outlaw it, as they superseded many localized festivals.

At any rate, if you let such a cat out of the bag, chaos ensues, as you have a very angry cat. So the expression means, letting something out verbally that will disrupt things considerably. --mvzp

By anon107468 — On Aug 30, 2010

Keeping in mind that phrases like letting the cat out of the bag can potentially have many points of origin (such as the phrase "the whole nine yards").

I was told letting the cat out of the bag did have to do with a whip but it was with the Army and not the navy. in the 19th century, the head drummer in an army regiment known as the drum major was known to have carried the cat of nine tails in a bag tied to his belt. thus when "letting the cat out of the bag" it could mean that someone has gotten themselves into trouble.

By anon77124 — On Apr 13, 2010

Traditionally the cat-o-nine-tails was kept in a special bag. When the cat was "out of the bag", it meant that someone (who's secret, or crime, is revealed) was about to be punished. This medieval theory about markets is too complicated, the thing about kids and kittens is ridiculous and sending messages by tattoos on cats -- you can't be serious!

By anon68594 — On Mar 03, 2010

you all seem to forget that this phrase origins are, indeed, from the medieval times.

By anon63940 — On Feb 04, 2010

I think this comment means to tell a secret that should not have been told which happens a lot with my friends and me.

By anon63939 — On Feb 04, 2010

I think this website helped me a lot.

By anon60298 — On Jan 13, 2010

I've used the phrase for a slightly different meaning, but I figure I'm wrong: It's damn hard to get a cat into a bag in the first place (and especially a second time) but easy to get it out (it will run out of its own accord). Hence I use it to mean e.g. informing people about a secret. It's damn hard to "un-publish" something that people already know about.

I don't believe that anon26308's comment is true at all, not just for cruelty reasons. It's a very slow process compared to how you could manufacture other means for transporting secret messages.

By anon51905 — On Nov 10, 2009

Cats reproduce at a considerable rate. now we have humane ways of controlling the population but this was not always so. In the past, a common way of dealing with unwanted kittens was to place them in a bag and drown them.

Children of course tend to get very emotional about such things, so secrecy was usually required. To let the cat out of the bag is to suddenly find yourself responsible for the care and feeding of a whole bunch of unwanted cats or risk traumatizing your children.

I think that Occam's razor works pretty well here.

By anon26308 — On Feb 11, 2009

The term cat out of the bag actually refers to the secret ways they used to send information to each other back in medieval days. They would shave a cat, then tattoo messages on the cat. They would put the cat in the bag until the hair grew back to cover the messages. If you let the cat out of the bag too early, you can see the secrets.

By anon22762 — On Dec 09, 2008

"Removing a whip from a bag is clearly not a euphemism for revealing a secret or spoiling a scam."

Unless that secret scam was mutiny. I could well imagine secret plotters fearing the removal of said whip. I could easily envision one conspirator whispering, "Keep quiet, lest ye let the cat out of the bag."

Considering furthermore that the origins of the phrase "Not enough room to swing a dead cat" hearkens back to the aforementioned cat-o-nine-tails. Smaller rooms on board did not provide enough room to wield the whip effectively, and therefore, there was not enough room to swing the cat. (The phrase evolved through usage to include the "dead" part. Apparently people don't like cats much.)

As to your initial hypothesis ... have you ever put a cat in a bag? They are not known to be patient animals who take kindly to confinement. Cats have claws and teeth, and their usual first reaction to any form of distress is to use them to good effect.

Can you imagine someone buying a pig - which, even small, must weigh a good 40-50 pounds or so - and, even in a bag, not being able to tell the difference from a cat?

And can you further then imagine that pig-mimicking cat staying in the bag quietly, silently, biding its time?

Doesn't seem to add up to me.

Furthermore, people in Medieval times tended to live close together. They lived and worked and traded together on a more or less constant basis. People just didn't travel much.

Not to say that people didn't cheat each other back then, but odds are if you buy a goat, somehow mistake a cat in a bag for a goat in a bag, and then walk all the way home before finding out you've been swindled ... well, you're going to just turn around and go back again and raise some royal hell.

Mary McMahon
Mary McMahon

Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a...

Learn more
Language & Humanities, in your inbox

Our latest articles, guides, and more, delivered daily.

Language & Humanities, in your inbox

Our latest articles, guides, and more, delivered daily.