Idioms are special phrases whose meanings cannot be understood by translating each word literally.
Instead, they carry figurative meanings that native speakers instantly recognize. For example,
when someone says something is “a long shot,” they don’t mean a physical distance—they mean the chance of success is very small.
Learning idioms is one of the fastest ways to sound natural and fluent in English. They appear everywhere: in conversations,
business communication, movies, academic discussions, and even professional writing. In particular, idioms for impossible situations help you describe challenges,
unrealistic expectations, and unlikely outcomes in a colorful and memorable way.
If you’re trying to expand your vocabulary, mastering English idioms for impossible situations,
expressions for difficult situations, and advanced English idioms can significantly improve your communication skills.
Instead of simply saying “this cannot happen,” idioms allow you to express the same idea with personality, humor, or emphasis.
In this guide, you’ll discover 13 powerful idioms used to describe situations that are extremely difficult—or nearly impossible—to achieve.
Each idiom includes real-life examples, usage tips, and related expressions so you can confidently use them in everyday conversations.
Quick Overview Table
| Idiom | Short Meaning | Tone | Common Use Context |
|---|---|---|---|
| When pigs fly | Something will never happen | Informal | Casual conversation |
| A snowball’s chance in hell | Almost zero possibility | Informal | Strong disbelief |
| Mission impossible | Extremely difficult task | Neutral | Work, projects |
| Beating a dead horse | Trying something that cannot succeed | Informal | Arguments, debates |
| Like finding a needle in a haystack | Extremely hard to locate | Neutral | Searching for something |
| Against all odds | Success despite impossibility | Neutral | Inspirational situations |
| Climbing Mount Everest | A task requiring huge effort | Neutral | Big goals |
| Catch the wind | Trying to achieve the uncatchable | Literary | Creative writing |
| Move heaven and earth | Attempt everything possible | Semi-formal | Determined efforts |
| Square the circle | Solve an impossible problem | Formal | Academic/business |
| Not in a million years | Absolutely impossible | Informal | Personal reactions |
| Pull a rabbit out of a hat | Achieve something unexpectedly | Neutral | Problem solving |
| Chasing the impossible | Pursuing unrealistic goals | Neutral | Motivation discussions |
When Pigs Fly
Meaning:
Used to say that something will never happen or is extremely unrealistic.
When to Use It:
In casual conversations when someone suggests an idea that seems completely unrealistic.
Example Sentence:
“He thinks he’ll finish that entire project overnight—yeah, when pigs fly.”
Similar Expressions:
• Not in a million years
• Fat chance
Opposite Expression:
A sure thing
A Snowball’s Chance in Hell
Meaning:
Describes a situation where the possibility of success is almost zero.
When to Use It:
When discussing extremely unlikely outcomes, especially in competitive or risky situations.
Example Sentence:
“The small startup had a snowball’s chance in hell of beating the global corporation.”
Similar Expressions:
• Slim chance
• Long shot
Opposite Expression:
Highly likely
Mission Impossible
Meaning:
A task that appears nearly impossible due to difficulty or complexity.
When to Use It:
In professional or personal contexts when a goal feels extremely demanding.
Example Sentence:
“Completing three months of work in two days felt like a mission impossible.”
Similar Expressions:
• Herculean task
• Uphill battle
Opposite Expression:
Easy job
Beating a Dead Horse
Meaning:
Continuing to push an idea or effort that has already failed.
When to Use It:
In discussions when people keep arguing about something that cannot change.
Example Sentence:
“We already rejected the proposal—discussing it again is just beating a dead horse.”
Similar Expressions:
• Fighting a losing battle
• Wasting energy
Opposite Expression:
Start fresh
Like Finding a Needle in a Haystack
Meaning:
Trying to find something extremely rare or difficult to locate.
When to Use It:
When searching through a large amount of information or objects.
Example Sentence:
“Finding the correct document in that messy archive was like finding a needle in a haystack.”
Similar Expressions:
• Almost impossible to find
• Hidden gem
Opposite Expression:
Easy to locate
Against All Odds
Meaning:
Achieving success despite major obstacles or impossibilities.
When to Use It:
Often used in motivational or inspirational stories.
Example Sentence:
“Against all odds, the underdog team won the championship.”
Similar Expressions:
• Defy the odds
• Beat the impossible
Opposite Expression:
Expected outcome
Climbing Mount Everest
Meaning:
A metaphor for an extremely difficult challenge requiring determination.
When to Use It:
To describe goals that demand enormous effort.
Example Sentence:
“Starting a company with no funding felt like climbing Mount Everest.”
Similar Expressions:
• Monumental task
• Huge challenge
Opposite Expression:
Walk in the park
Catch the Wind
Meaning:
Trying to achieve something that cannot realistically be captured or controlled.
When to Use It:
Often used in creative writing or reflective discussions.
Example Sentence:
“Trying to control every outcome in life is like trying to catch the wind.”
Similar Expressions:
• Impossible pursuit
• Futile effort
Opposite Expression:
Within reach
Move Heaven and Earth
Meaning:
To try every possible method to achieve something difficult.
When to Use It:
When someone is extremely determined to succeed.
Example Sentence:
“She moved heaven and earth to secure the scholarship.”
Similar Expressions:
• Do everything possible
• Leave no stone unturned
Opposite Expression:
Give up easily
Square the Circle
Meaning:
Attempting to solve a problem that seems logically impossible.
When to Use It:
In academic, business, or analytical discussions.
Example Sentence:
“The manager tried to square the circle by reducing costs while increasing quality.”
Similar Expressions:
• Impossible puzzle
• Logical paradox
Opposite Expression:
Simple solution
Not in a Million Years
Meaning:
Something that will definitely never happen.
When to Use It:
Strongly rejecting a suggestion or possibility.
Example Sentence:
“I would not quit my career for that risky idea—not in a million years.”
Similar Expressions:
• Absolutely not
• No chance
Opposite Expression:
Definitely yes
Pull a Rabbit Out of a Hat
Meaning:
To produce an unexpected solution to a difficult problem.
When to Use It:
When someone finds a surprising way to solve an impossible situation.
Example Sentence:
“The engineer pulled a rabbit out of a hat and fixed the system minutes before launch.”
Similar Expressions:
• Unexpected miracle
• Clever trick
Opposite Expression:
Fail completely
Chasing the Impossible
Meaning:
Pursuing goals that are unrealistic or unattainable.
When to Use It:
When someone invests energy in something that is unlikely to succeed.
Example Sentence:
“He spent years chasing the impossible instead of building realistic plans.”
Similar Expressions:
• Unrealistic dream
• Impossible pursuit
Opposite Expression:
Achievable goal
Categorizing the Idioms
Idioms for Difficult Situations
- Mission impossible
- Square the circle
- Climbing Mount Everest
- Move heaven and earth
Idioms for Impossible Outcomes
- When pigs fly
- A snowball’s chance in hell
- Not in a million years
Idioms for Futile Efforts
- Beating a dead horse
- Catch the wind
- Chasing the impossible
Idioms for Rare Success
- Against all odds
- Pull a rabbit out of a hat
- Like finding a needle in a haystack
How to Use These Idioms in Real Conversations
Workplace Example
“Our team has only two days to redesign the product. It feels like a mission impossible, but we’ll try to move heaven and earth.”
Casual Conversation
“Winning the lottery twice? That will happen when pigs fly.”
Writing Example (Email)
“Finding the error in thousands of lines of code felt like finding a needle in a haystack, but we eventually solved the issue.”
IELTS / Exam Tip
Using idioms naturally can boost your speaking score, especially in the IELTS Speaking Part 3, where expressing opinions about challenges or possibilities is common.
Common Mistakes to Avoid
Literal Misunderstanding
Idioms should not be interpreted word-for-word. “When pigs fly” does not actually involve animals.
Wrong Tone Usage
Some idioms like “a snowball’s chance in hell” are informal and may sound rude in professional writing.
Formal vs Informal Confusion
Idioms like “square the circle” work well in academic discussions, while “when pigs fly” is better suited to casual speech.
Practice Exercise
Fill in the Blank
- Finishing this report tonight feels like ________.
- He keeps arguing even though the decision is final. He’s ________.
- Winning that competition was success ________.
- Finding the right file was like ________.
- She tried to ________ to help her friend get the job.
- That idea will happen ________.
- Solving the budget problem felt like trying to ________.
- The engineer managed to ________ and fix the problem.
- Searching for that rare coin is like ________.
- He spent years ________ instead of making practical plans.
Multiple Choice
- Which idiom means “almost impossible”?
A. Move heaven and earth
B. A snowball’s chance in hell
C. Pull a rabbit out of a hat - Which idiom describes solving a very complex problem?
A. Square the circle
B. When pigs fly
C. Catch the wind - Which idiom means trying everything possible?
A. Move heaven and earth
B. Beat the odds
C. Catch the wind - Which idiom means searching for something extremely rare?
A. Long shot
B. Needle in a haystack
C. Beating a dead horse - Which idiom refers to continuing a pointless effort?
A. Against all odds
B. Beating a dead horse
C. Pull a rabbit out of a hat
Writing Prompts
- Write a short paragraph describing a difficult goal using two idioms from the list.
- Describe a time when success happened against all odds.
- Write a short dialogue between two friends discussing an impossible idea.
Answers
Fill in the Blank
- mission impossible
- beating a dead horse
- against all odds
- finding a needle in a haystack
- move heaven and earth
- when pigs fly
- square the circle
- pull a rabbit out of a hat
- finding a needle in a haystack
- chasing the impossible
Multiple Choice
- B
- A
- A
- B
- B
FAQs
What are idioms for impossible situations?
They are figurative expressions used to describe events, goals, or outcomes that are extremely difficult or unlikely to happen.
Why should English learners study idioms?
Idioms make your speech sound more natural and help you understand native conversations, movies, and books.
Are idioms appropriate in formal writing?
Some are. Expressions like “square the circle” can appear in professional writing, but very casual idioms should be avoided.
How can I remember idioms easily?
Learning them through real examples, stories, and conversations helps them stick in memory better than memorizing definitions.
Are idioms important for IELTS or speaking exams?
Yes. Using idioms naturally can improve fluency and lexical resource scores in English proficiency exams.
Conclusion
Idioms add color, emotion, and personality to the English language. Instead of simply saying something is impossible,
expressions like “when pigs fly,” “mission impossible,” or “a snowball’s chance in hell” allow you to communicate the same idea in a vivid and memorable way.
By learning topic-based idioms—such as those related to impossible situations—you not only improve vocabulary but also develop more natural speaking and writing skills.
The key is to practice using them in real conversations, emails, and storytelling so they become part of your everyday language.
With regular exposure and practice, these idioms will help you express complex ideas with confidence and fluency.
Corvin Hale is a language enthusiast who makes learning English idioms simple and fun.
