English idioms: meanings and examples
Short answer: An idiom is a fixed phrase whose meaning is different from its words. “A piece of cake” is not about cake: it means something is very easy. This guide explains 99 common English idioms and everyday expressions in simple English, grouped by what you want to say, with examples and the mistakes learners make.
At a glance
| Idiom | Meaning | Example |
|---|---|---|
| A piece of cake | very easy | Don't worry about the quiz. It is a piece of cake. |
| Break the ice | help people who do not know each other relax | A short game helped us break the ice at the meeting. |
| Under the weather | a little sick | I'm feeling under the weather today, so I will stay home. |
| Spill the beans | tell a secret | Please don't spill the beans about the surprise. |
| Hit the books | study hard | I have a test on Friday, so I need to hit the books. |
| Once in a blue moon | not often at all | We eat out once in a blue moon. |
What is an idiom?
An idiom is a group of words that people use together with a special meaning. If you translate it word for word, it usually makes no sense. Learn an idiom as one piece, like a single long word, and learn it with one sentence of your own.
How do you understand an idiom you hear?
- Look at the whole sentence and the situation, not at each word.
- Ask yourself: does the literal meaning make sense here? If it does not, it is probably an idiom.
- Check the meaning in a dictionary or a lesson, then say one new sentence with it.
- Do not translate it word for word into your own language.
Are idioms formal or informal?
Most idioms are fine in speech, in friendly emails and in stories. Some are very casual and sound strange in a formal report or a test essay, for example “hit the hay” or “my bad”. In formal writing, use idioms rarely. When you are not sure, use a plain phrase instead: “go to bed”, or “sorry, that was my mistake”.
Common mistakes with idioms
- Changing a word. An idiom is fixed, so say “a piece of cake”, not “a piece of pie”.
- Taking the words literally. “It's raining cats and dogs” is about very heavy rain, not about animals.
- Using the wrong small word. Say “on cloud nine”, not “in cloud nine”.
- Mixing up idioms with the same idea. “Spill the beans” and “let the cat out of the bag” both mean to tell a secret, but the second one is usually by mistake.
- Using too many in one text. One idiom is enough for a short message; many sound forced.
Idioms about feelings
Use these to say that you are very happy, sad, nervous or stressed.
| Expression | Meaning |
|---|---|
| On cloud nine | Very, very happy |
| Over the moon | Very, very happy |
| Down in the dumps | Feeling very sad |
| Have butterflies in your stomach | To feel nervous, sometimes excited, before something |
| Get cold feet | To become afraid before doing something you planned |
| Blow off steam | To do something that helps you feel less angry or stressed |
| Get something off your chest | To tell someone a worry that you have kept inside |
| Pull yourself together | To calm down and control your feelings |
Idioms about feelings: meanings and examples
Idioms for talking with people
These are for starting a conversation, sharing secrets, saying what you think and agreeing or disagreeing.
| Expression | Meaning |
|---|---|
| Break the ice | To help people who do not know each other feel comfortable |
| Spill the beans | To tell a secret |
| Let the cat out of the bag | To tell a secret by mistake |
| Hit the nail on the head | To say exactly what is right or true |
| Beat around the bush | To not say the main thing directly |
| All ears | Ready to listen carefully |
| Pull someone's leg | To joke with someone and say something that is not true |
| Make a long story short | To tell only the most important parts of a long story |
| Ring a bell | You think you have heard or seen it before |
| Speak of the devil | Said when someone you were talking about appears |
| It's a small world | Said when you meet someone in a surprising way |
| Steal someone's thunder | To get attention or praise that another person should get |
| See eye to eye | To agree with someone |
| On the same page | To understand or agree about something in the same way |
| In the same boat | Having the same problem as someone else |
| It takes two to tango | Both people may share blame for a problem |
| Give someone the benefit of the doubt | To believe someone might be right even when you are unsure |
| A hard nut to crack | A person or problem that is hard to understand |
Idioms for talking with people: meanings and examples
Idioms for school and work
These are for studying, doing a job, making an effort and starting again when a plan fails.
| Expression | Meaning |
|---|---|
| Hit the books | To study hard |
| Burn the midnight oil | To work or study late at night |
| Pass with flying colors | To do very well in a test or exam |
| Learn the ropes | To learn how to do a new job or activity |
| Call it a day | To stop working for now |
| Cut corners | To do something cheaply or too quickly, often badly |
| Go back to the drawing board | To start again because the plan did not work |
| Get the ball rolling | To start something |
| Go the extra mile | To do more than people expect |
| Bite off more than you can chew | To try to do more than you can do |
| Bend over backwards | To try very hard to help someone |
| Think outside the box | To think in a new and different way |
| Get the hang of it | To learn how to do something well enough |
| Kill two birds with one stone | To achieve two things with one action |
Idioms for school and work: meanings and examples
Idioms about money
These are for talking about prices, about having no money and about things that are free or common.
| Expression | Meaning |
|---|---|
| Cost an arm and a leg | To cost a lot of money |
| A dime a dozen | Something very common and easy to find |
| Bucks | Dollars |
| Broke | Having no money |
| Freebie | Something you get for free |
Idioms about money: meanings and examples
Idioms for advice and encouragement
Use these to wish someone luck, to cheer them up or to tell them not to worry.
| Expression | Meaning |
|---|---|
| Break a leg | A way to say good luck, especially before a show |
| Hang in there | Do not give up when things are hard |
| Keep your chin up | Stay hopeful when things are hard |
| Take it easy | Relax; do not worry |
| Cry over spilled milk | To feel bad about something that cannot be changed |
| Cross that bridge when you come to it | Wait to solve a problem until it really happens |
| Easy does it | Slow down; be careful and gentle |
| Let sleeping dogs lie | Do not bring up old problems |
| Cut someone some slack | To be kind and not too strict with someone |
| Bite the bullet | To do something hard or scary because you must |
| Give it a shot / Give it a try | To try something |
Idioms for advice and encouragement: meanings and examples
Idioms about luck, risk and choices
These are for hoping for luck, taking a risk, choosing a side and losing a chance.
| Expression | Meaning |
|---|---|
| Keep your fingers crossed | Hope for good luck |
| On thin ice | Close to getting into trouble |
| Put all your eggs in one basket | To risk everything on one plan |
| Sit on the fence | To not choose a side |
| The ball is in your court | Now it is your turn to act or decide |
| Miss the boat | To lose a chance |
| The best of both worlds | To enjoy the good parts of two different things |
| Jump on the bandwagon | To do something because many others are doing it |
Idioms about luck, risk and choices: meanings and examples
Idioms about mistakes and trouble
These are for talking about blame, getting into trouble, making a problem worse and giving up.
| Expression | Meaning |
|---|---|
| Barking up the wrong tree | To blame or ask the wrong person |
| In hot water | In trouble |
| Caught red-handed | Caught while doing something wrong |
| Add fuel to the fire | To make a bad problem worse |
| Bite the dust | To fail, lose, or stop working |
| Throw in the towel | Give up |
| Get out of hand | To become hard to control |
Idioms about mistakes and trouble: meanings and examples
Idioms about everyday life, time and weather
These are for easy things, rare things, sudden things, sleep, weather and well-known sayings about life.
| Expression | Meaning |
|---|---|
| A piece of cake | Something that is very easy to do |
| Under the weather | Feeling a little sick |
| Once in a blue moon | Not often at all |
| Hit the road | To leave or start a trip |
| Keep an eye on | To watch someone or something to keep them safe |
| Out of the blue | Suddenly, when you did not expect it |
| Raining cats and dogs | Raining very hard |
| Hit the hay / Hit the sack | To go to bed |
| When pigs fly | Said about something you think will never happen |
| Better late than never | Doing something late is better than not doing it |
| A blessing in disguise | Something bad happens but brings something good later |
| Actions speak louder than words | What you do matters more than what you say |
| The early bird catches the worm | People who start early often have a better chance |
| No pain, no gain | You must work hard to get good results |
| A picture is worth a thousand words | A picture can explain an idea better than words |
| Every cloud has a silver lining | Something good can come from a bad time |
Idioms about everyday life, time and weather: meanings and examples
Everyday expressions (informal)
These are not classic idioms, but you hear them all the time. They are informal: fine with friends and in casual messages, and less good in formal writing.
| Expression | Meaning |
|---|---|
| Cool | Very good; great |
| Awesome | Very good; amazing |
| Dude | An informal way to call a friend or person |
| What's up? | A friendly way to say hello or ask what is happening |
| Chill / Chill out | Relax; stay calm |
| Hang out | To spend free time with friends |
| My bad | I made a mistake. Sorry |
| No worries / No biggie | It is okay. Do not worry |
| Bummer | Something bad or disappointing has happened |
| Lame | Not good or interesting (can sound rude) |
| Couch potato | Someone who spends a lot of time sitting and watching TV |
| Vibe / Vibes | The feeling you get from a place or person |
Everyday English expressions: cool, my bad, no worries and more
Compare similar idioms
“A piece of cake” and other idioms for easy things: which one to use?
Idioms or slang?
Idioms stay in use for a long time and most are fine in everyday speech. Slang changes fast and is very informal. If you want to understand the words you hear in songs, videos and online chat, read the English slang guide. If you want to use idioms in your own writing, see the English writing guide.
Questions
What is an idiom in English?
An idiom is a fixed group of words with a meaning that is different from the meaning of the separate words. For example, “under the weather” means a little sick, and it has nothing to do with the sky.
What does “a piece of cake” mean?
It means something is very easy to do. You can say it about a test, a job or a game: “The homework was a piece of cake.”
What does “break the ice” mean?
It means to help people who do not know each other feel comfortable, for example with a joke, a question or a short game at the start of a meeting.
Which idioms should I learn first?
Start with short ones you can use every day: “a piece of cake”, “break the ice”, “under the weather”, “hit the books” and “once in a blue moon”. Then add idioms for the places where you use English most, such as school, work or travel.
Can I use idioms in formal writing?
Use them rarely. A few well-known idioms are fine in a friendly email or a story, but formal reports and test essays are clearer with plain words. Very casual expressions such as “hit the hay” are better in speech.
What is the difference between an idiom and slang?
An idiom is a fixed phrase that people use for a long time. Slang is a very informal word or phrase that changes fast and belongs to friends and online talk. Slang is not for school, work or formal writing.
How can I practice idioms on English for Fun?
The Idioms tool in the Learning Path has 99 short lessons. In each lesson you hear the idiom, learn its meaning in English, use it in a sentence, choose the right situation and say it yourself. The first lesson, “A piece of cake”, is free to try; the rest is part of Full Access.
Part of the 💬 Idioms tool. Đọc bằng tiếng Việt.
Written for English learners by the English for Fun team. How we write our lessons · Last updated 2026-11-05.