Idioms are fun figures of speech where the words together have a different meaning than what they say literally. People use them every day to make speaking and writing much more colorful and exciting. In this article, you will learn fifty special expressions connected to impossibilities, dreams, and things that are never going to happen.
In this lesson, we’ll look at idioms that mean total impossibilities, absurd ideas, or things that will never occur. Let’s get started and explore some of these helpful expressions.
Idioms for Never Going to Happen
1. When pigs fly
Definition: Something that is completely impossible and will never take place in reality.
Definition: Something that is completely impossible and will never take place in reality.
Used in a Sentence: My little brother said he would clean his room when pigs fly. / Expecting our school to cancel all homework forever will happen when pigs fly.
Similar Expressions: Never in a million years / Total impossibility
2. When hell freezes over
Definition: A humorous way to say an event is never going to happen under any circumstances.
Used in a Sentence: He told me he would lend me his rare video game when hell freezes over. / We will stop eating ice cream on hot summer days when hell freezes over.
Similar Expressions: Absolutely never / Unlikely ever
3. A cold day in July
Definition: An expression describing an event that is completely impossible because of the weather or logic.
Used in a Sentence: Thinking that our lazy dog will run a marathon is like expecting a cold day in July. / He said he would eat plain broccoli without complaint on a cold day in July.
Similar Expressions: Never going to happen / Impossible event
4. Not in a million years
Definition: A strong phrase meaning something will never occur at any point in the future.
Used in a Sentence: Not in a million years would I jump off the high diving board into the deep pool. / She said she would not in a million years wear a clown suit to class.
Similar Expressions: Absolutely not / Never ever
5. Fat chance
Definition: A sarcastic way of saying there is almost zero probability of something happening.
Used in a Sentence: When I asked my older brother if I could borrow his brand new skateboard, he just laughed and said, “Fat chance.” / Fat chance we are getting extra recess after arriving late to class.
Similar Expressions: Highly unlikely / Almost zero chance
6. Snowball’s chance in hell
Definition: Having zero chance of survival or success in a difficult or impossible situation.
Used in a Sentence: Trying to keep an ice cube from melting on a hot pavement has a snowball’s chance in hell. / Without practicing our math tables, our team had a snowball’s chance in hell of winning the quiz.
Similar Expressions: Zero chance / Impossible odds
7. Catch a falling star
Definition: Attempting something so physically impossible that it can never be achieved.
Used in a Sentence: Trying to reach up and catch a falling star from our treehouse is never going to happen. / He wished he could catch a falling star to make his toy magically fix itself.
Similar Expressions: Impossible quest / Unattainable goal
8. Touch the moon
Definition: A poetic way to describe trying to reach a goal that is entirely out of reach.
Used in a Sentence: Jumping off the slide and hoping to touch the moon is never going to happen. / Setting goals you cannot physically reach is like trying to touch the moon.
Similar Expressions: Reach impossibilities / Unreachable dream
9. Till cows come home
Definition: Waiting for an event that is so far away or unlikely that it may never occur.
Used in a Sentence: You can ask me to eat plain spinach till cows come home, but I still will not like it. / He can practice his magic tricks till cows come home, but rabbits won’t magically appear.
Similar Expressions: Forever and ever / Endless wait
10. Once in a blue moon
Definition: An event so exceptionally rare that it practically never happens in ordinary life.
Used in a Sentence: Getting our whole extended family to agree on one movie happens only once in a blue moon. / Seeing a shooting star during daylight is like finding something once in a blue moon.
Similar Expressions: Very rarely / Extremely seldom
11. Leap over the moon
Definition: An absurd exaggeration of an action that is completely physically impossible.
Used in a Sentence: Expecting our pet cat to stand on two legs and leap over the moon is never going to happen. / He joked that he could jump so high he would leap over the moon.
Similar Expressions: Impossible jump / Absurd feat
12. Turn water into wine
Definition: A miraculous feat that is never going to happen in everyday real life.
Used in a Sentence: Expecting my science experiment to magically turn water into soda is never going to happen. / Magic tricks are fun, but nobody can truly turn water into wine.
Similar Expressions: Magical impossibility / Unreal feat
13. Pull yourself up by your bootstraps to Mars
Definition: An exaggerated phrase for a goal that is far beyond human capability.
Used in a Sentence: Thinking you can build a spaceship in your backyard and fly to Mars is never going to happen. / Setting expectations that high is like trying to pull yourself up to Mars.
Similar Expressions: Unrealistic goal / Impossible ambition
14. Reach for the stars and grab one
Definition: A poetic idiom about an ambition that sounds wonderful but is physically impossible.
Used in a Sentence: My little sister thinks she can reach for the stars and grab one for her room, but that is never going to happen. / Wishing on a star is fun, but you cannot physically reach for the stars and grab one.
Similar Expressions: Impossible wish / Unattainable dream
15. Straight from the horse’s mouth
Definition: While this usually means reliable news, trying to get news from a real talking horse is never going to happen.
Used in a Sentence: Expecting our family dog to talk to us straight from the horse’s mouth is never going to happen. / Animals do not speak English, so getting news straight from a pet’s mouth is impossible.
Similar Expressions: Impossible source / Unreal expectation
16. Build Rome in a minute
Definition: An impossible timeline modification of a famous saying about speed and grand tasks.
Used in a Sentence: Expecting me to clean the entire messy garage in one minute will never happen because you cannot build Rome in a minute. / Writing a whole novel in ten minutes is like trying to build Rome in a minute.
Similar Expressions: Impossible speed / Unrealistic timeline
17. Climb Mount Everest in flip-flops
Definition: Attempting an extremely dangerous and absurd feat that is never going to work out.
Used in a Sentence: Trying to climb Mount Everest in flip-flops during a snowstorm is never going to happen. / Walking across hot desert sand without shoes is like trying to climb Everest in slippers.
Similar Expressions: Foolish attempt / Impossible task
18. Make a silk purse out of a sow’s ear
Definition: An old expression meaning you cannot turn something low quality into something luxurious.
Used in a Sentence: Trying to turn my broken cardboard box into a shiny luxury toy is like trying to make a silk purse out of a sow’s ear. / Fixing that ancient broken bicycle completely is like making a silk purse out of a sow’s ear.
Similar Expressions: Impossible transformation / Hopeless upgrade
19. Talk the legs off a chair
Definition: While talkative people exist, expecting wooden furniture to walk away after chatting is never going to happen.
Used in a Sentence: My friend loves to chat, but expecting her words to actually talk the legs off a chair is never going to happen. / Furniture cannot move, no matter how much you talk to it.
Similar Expressions: Silly exaggeration / Unreal notion
20. Count your chickens before they hatch
Definition: Assuming an outcome will happen when it is still entirely uncertain or impossible to guarantee.
Used in a Sentence: Don’t assume you won the art contest and count your chickens before they hatch. / Planning a celebration before passing the exam is like counting your chickens before they hatch.
Similar Expressions: Assume too soon / Count uncertain gains
21. Whistle Dixie
Definition: An idiom sometimes used to mean hoping for an impossible or unrealistic outcome.
Used in a Sentence: If you think the teacher will cancel math tests forever, you are just whistling Dixie. / Hoping that chores will do themselves while you sleep is like whistling Dixie.
Similar Expressions: Dream idly / Wish vainly
22. Bark up the wrong tree
Definition: Searching for a solution in a place where it will never be found.
Used in a Sentence: If you think you will find my lost homework inside the refrigerator, you are barking up the wrong tree. / Looking for your missing red crayon in the freezer means you are barking up the wrong tree.
Similar Expressions: Look in vain / Search wrongly
23. Chase rainbows
Definition: Spending all your time pursuing wild, impossible dreams that will never materialize.
Used in a Sentence: Spending your entire allowance trying to win an impossible carnival game is just chasing rainbows. / Instead of studying real subjects, he spent his youth chasing rainbows.
Similar Expressions: Pursue illusions / Waste effort
24. A wild goose chase
Definition: Following a hopeless trail that leads to an outcome that is never going to happen.
Used in a Sentence: Looking for my missing red crayon in the massive gravel parking lot turned out to be a wild goose chase. / The confusing treasure map sent us on a wild goose chase around an empty playground.
Similar Expressions: Hopeless search / Foolish errand
25. Build castles in the air
Definition: Daydreaming about grand, impossible plans that will never actually be built.
Used in a Sentence: Sitting in math class building castles in the air about owning a flying car will never help you pass. / Stop building castles in the air and focus on your actual homework assignment.
Similar Expressions: Idle daydreams / Unreal plans
26. Pie in the sky
Definition: An extravagant promise or dream that is never going to become reality.
Used in a Sentence: The idea that our school lunchroom would serve pizza every single day was just pie in the sky. / Promising everyone a pet pony for the classroom is pure pie in the sky.
Similar Expressions: Unrealistic dream / Empty promise
27. Fish in the desert
Definition: Looking for something in a location where it can never possibly exist.
Used in a Sentence: Expecting to catch a fresh trout by digging a hole in the dry sandbox is like trying to fish in the desert. / Looking for snow gloves in a tropical rainforest is like trying to fish in the desert.
Similar Expressions: Impossible search / Wrong place
28. Square a circle
Definition: Attempting a geometric impossibility that math proves can never happen.
Used in a Sentence: Trying to convince my little brother that bedtime is fun is like trying to square a circle. / Solving that riddle with the current rules is like trying to square a circle.
Similar Expressions: Mathematical impossibility / Impossible puzzle
29. Water flows uphill
Definition: A natural law violation representing something that is never going to happen.
Used in a Sentence: Expecting the river behind our school to reverse direction and water flow uphill is never going to happen. / Gravity ensures that water never flows uphill on its own.
Similar Expressions: Defy nature / Impossible direction
30. A leopard changes its spots
Definition: The belief that someone’s core personality will suddenly and completely change, which rarely happens.
Used in a Sentence: Expecting our messy classmate to suddenly become neat overnight is like believing a leopard changes its spots. / People can improve habits, but pretending a leopard changes its spots instantly is unrealistic.
Similar Expressions: Permanent traits / Unchanging nature
31. Put toothpaste back in the tube
Definition: Trying to reverse an action that is completely irreversible and impossible to undo.
Used in a Sentence: Spreading rumors and trying to take them back is like trying to put toothpaste back in the tube. / Once you break the glass cup, you cannot put toothpaste back in the tube.
Similar Expressions: Irreversible action / Cannot undo
32. Hen’s teeth
Definition: Something that does not exist anywhere in the world and can never be found.
Used in a Sentence: Finding a free ticket to the sold-out concert on the sidewalk is as rare as hen’s teeth. / Honest answers from my little brother about who ate the cookie are as scarce as hen’s teeth.
Similar Expressions: Nonexistent / Extremely rare
33. Rocking horse manure
Definition: A humorous slang phrase for something that is completely fictional and impossible to find.
Used in a Sentence: Expecting to find a working time machine at the garage sale is like searching for rocking horse manure. / That rare trading card is as scarce as rocking horse manure.
Similar Expressions: Total fiction / Nonexistent item
34. Whistling past the graveyard
Definition: Pretending that a terrible problem does not exist when disaster is bound to happen.
Used in a Sentence: Ignoring your failing math grade before report card day is just whistling past the graveyard. / Walking into the exam without studying while whistling past the graveyard won’t help.
Similar Expressions: Ignore danger / False bravery
35. Buy the Brooklyn Bridge
Definition: Being foolish enough to believe someone’s impossible, fake sales pitch.
Used in a Sentence: If you think I am going to sell you my invisible pet dragon, you must think you can buy the Brooklyn Bridge. / He tried to sell me a fake golden coin, thinking I would buy the Brooklyn Bridge.
Similar Expressions: Fall for a scam / Believe a lie
36. Sell ice to an Eskimo
Definition: Trying to accomplish a completely pointless and impossible sales task.
Used in a Sentence: Trying to convince our art teacher to buy extra paint brushes she already has is like trying to sell ice to an Eskimo. / Marketing winter coats in the middle of a desert is like trying to sell ice to an Eskimo.
Similar Expressions: Pointless pitch / Useless sale
37. Carry water in a sieve
Definition: Attempting a task that is designed to fail completely and hold nothing.
Used in a Sentence: Trying to keep secrets with my chatty classmates is like trying to carry water in a sieve. / Writing notes on dissolving paper in the rain is like carrying water in a sieve.
Similar Expressions: Doomed task / Futile effort
38. Teach a fish to climb a tree
Definition: Trying to train someone in a skill that goes completely against their nature.
Used in a Sentence: Forcing our quiet librarian to star in an action movie is like trying to teach a fish to climb a tree. / Expecting our lazy basset hound to win a sprinting race is like teaching a fish to climb a tree.
Similar Expressions: Impossible training / Unnatural task
39. Pull a rabbit out of a hat without a hat
Definition: Trying to perform a miracle when you do not even have the basic tools required.
Used in a Sentence: Expecting me to bake a cake without flour, sugar, or an oven is like trying to pull a rabbit out of a hat without a hat. / Passing the exam without opening a textbook is like pulling a rabbit from a hat with no hat.
Similar Expressions: Miracle required / Missing tools
40. Keep water in a bottomless bucket
Definition: Spending energy on a task that drains away instantly with zero result.
Used in aSentence: Trying to save allowance money when you buy candy every single day is like keeping water in a bottomless bucket. / Studying for a test and forgetting everything instantly is like a bottomless bucket.
Similar Expressions: Waste effort / Endless drain
41. Catch the wind in a net
Definition: Trying to capture something intangible and impossible to hold.
Used in a Sentence: Trying to trap a secret rumor before it spreads across the school is like trying to catch the wind in a net. / Grasping abstract thoughts without writing them down is like catching the wind in a net.
Similar Expressions: Impossible capture / Intangible goal
42. See through a brick wall
Definition: Expecting to possess superhuman vision to solve a hidden mystery.
Used in a Sentence: Unless you can see through a brick wall, you have no way of knowing what surprise gift is inside that box. / Expecting the teacher to guess your thoughts without raising your hand is like seeing through a brick wall.
Similar Expressions: Impossible vision / Superhuman feat
43. Jump over your own shadow
Definition: An action that is physically impossible for any human or animal to perform.
Used in a Sentence: Telling someone to change their entire personality in one second is like asking them to jump over their own shadow. / Trying to outrun your own reflection on a sunny day is like jumping over your shadow.
Similar Expressions: Physical impossibility / Unreal action
44. Make bricks without straw
Definition: Trying to complete an important project while being denied the necessary materials.
Used in a Sentence: Asking our club to build a float without cardboard or scissors is like making bricks without straw. / Writing an essay without any reference books is like making bricks without straw.
Similar Expressions: Impossible conditions / Lacking supplies
45. Find a needle in a haystack
Definition: Searching for one tiny item in a massive pile where it is almost guaranteed never to be found.
Used in a Sentence: Looking for my lost contact lens in the giant school field grass felt like finding a needle in a haystack. / Trying to spot one specific ant on the playground is like finding a needle in a haystack.
Similar Expressions: Impossible search / Rare find
46. Build a stairway to heaven
Definition: A poetic phrase for an ambition so grand and unrealistic that it will never happen.
Used in a Sentence: Thinking you can build a stairway to heaven out of building blocks is a cute childhood dream that will never happen. / Setting career goals that defy all physics is like building a stairway to heaven.
Similar Expressions: Unreal ambition / Impossible structure
47. Ride a turtle to the moon
Definition: Using an absurdly slow method to attempt a completely impossible space journey.
Used in a Sentence: Expecting our old desktop computer to load this massive video game instantly is like trying to ride a turtle to the moon. / Finishing this fifty-page report in ten seconds is like riding a turtle to the moon.
Similar Expressions: Absurd method / Impossible journey
48. Teach an old dog new tricks
Definition: A common saying about how difficult it is to change someone’s established habits, though not entirely impossible, often joked about for stubborn people.
Used in a Sentence: Trying to get grandpa to text on a smartphone is like trying to teach an old dog new tricks. / He refused to change his cooking recipe, proving you cannot easily teach an old dog new tricks.
Similar Expressions: Stubborn habits / Hard to change
49. Put the cart before the horse
Definition: Doing things in the completely wrong order, making success impossible.
Used in a Sentence: Buying a trophy before the game is even played is putting the cart before the horse. / Trying to write the final essay conclusion before brainstorming ideas puts the cart before the horse.
Similar Expressions: Wrong order / Backward steps
50. Out of the blue lightning strike twice
Definition: Waiting for an extremely rare stroke of extreme luck to repeat itself immediately.
Used in a Sentence: Winning the school raffle two years in a row is like waiting for lightning to strike twice out of the blue. / Do not expect a miracle exam grade without studying, because lightning rarely strikes twice.
Similar Expressions: Rare coincidence / Unlikely repeat
Exercise to Practice
- My little brother said he would clean his room when pigs fly.
- He told me he would lend me his rare video game when hell freezes over.
- Thinking that our lazy dog will run a marathon is like expecting a gold coin to bake a cake.
- Not in a million years would I jump off the high diving board into the deep pool.
- When I asked my older brother if I could borrow his brand new skateboard, he just laughed and said, “Fat chance.”
- Trying to keep an ice cube from melting on a hot pavement has a snowball’s chance in hell.
- Trying to reach up and catch a falling star from our treehouse is never going to happen.
- Jumping off the slide and hoping to touch the moon is never going to happen.
- You can ask me to eat plain spinach till cows come home, but I still will not like it by riding a bicycle.
- Getting our whole extended family to agree on one movie happens only once in a blue moon.
- Expecting our pet cat to stand on two legs and leap over the moon is never going to happen.
- Expecting my science experiment to magically turn water into soda is never going to happen.
- Thinking you can build a spaceship in your backyard and fly to Mars is never going to happen.
- My little sister thinks she can reach for the stars and grab one for her room, but that is never going to happen.
- Expecting our family dog to talk to us straight from the horse’s mouth is never going to happen by reading a dictionary.
Answer Key
- True
- True
- False
- True
- True
- True
- True
- True
- False
- True
- True
- True
- True
- True
- False
Conclusion
Learning these idioms helps you understand English much better and gives you fun new ways to talk about impossibilities, dreams, and things that are never going to happen. You can use them when describing funny situations in stories, talking about exaggerated goals, or joking around with your friends and family.
Try using one or two of these expressions in a conversation or a story this week. Not only will your writing sound more exciting, but you will also have fun practicing your new skills.
Frequently Asked Questions
What are some common idioms for something never going to happen?
Some common idioms include when pigs fly, when hell freezes over, and not in a million years. These expressions are often used in everyday conversation to describe complete impossibilities.
Why do we use idioms in English?
Idioms make our language much more colorful, expressive, and fun than using plain words. They help us share big ideas and feelings in creative ways that people easily recognize.
How can I learn these idioms faster?
You can learn idioms faster by using them in daily sentences, writing short stories, and practicing with a friend. Making flashcards with pictures can also help you remember what each phrase means.
Are idioms used in everyday conversation?
Yes, native English speakers use idioms all the time during casual chats, television shows, and books. Learning them helps you understand jokes, stories, and conversations much more naturally.
Can idioms have more than one meaning?
Most idioms have one main accepted meaning, but how people use them can vary slightly depending on the context. Reading example sentences helps you see the exact way each phrase works.
