Common English Idioms and What They Mean

Quick Answer: Common English idioms are fixed expressions whose meaning you cannot guess from the words, such as a piece of cake (very easy), under the weather (a bit ill), break the ice (start a conversation) and cost an arm and a leg (very expensive). Learn each one as a complete unit with an example sentence, and use idioms mainly in informal speech, not formal writing.

Key takeaways

• Idioms are fixed: say a piece of cake, never a piece of pie or a cake.
• Small words matter: under the weather needs the, and it is raining cats and dogs, not dogs and cats.
• Break a leg means good luck, and it is used mainly before a performance or presentation.
• Some idioms are regional: over the moon sounds more British, a whole new ball game more American.
• One idiom in a conversation sounds natural; several in a row sound forced.
• In formal essays and exam writing, plain accurate English is safer than an idiom.

What is an idiom?

An idiom is a group of words with a meaning you cannot guess from the individual words. "Spill the beans" has nothing to do with beans: it means reveal a secret. Because of this, idioms must be learned as complete units, like phrasal verbs (see 30 everyday phrasal verbs).

Idioms about ease and difficulty

Idiom	Meaning	Example
a piece of cake	very easy	The test was a piece of cake.
no sweat	no problem, easy	"Can you help me move?" "No sweat."
easier said than done	harder than it sounds	Waking up at 5 every day? Easier said than done.
a tough nut to crack	a difficult problem or person	This math problem is a tough nut to crack.
learn the ropes	learn how to do a job	It took me a month to learn the ropes.

Idioms about health and feelings

Idiom	Meaning	Example
under the weather	slightly ill	I'm feeling a bit under the weather today.
on cloud nine	extremely happy	She's been on cloud nine since she got the job.
over the moon	very happy (common in UK)	We were over the moon with the news.
down in the dumps	sad	He's down in the dumps after the match.
get cold feet	become nervous before something big	He got cold feet before the wedding.

For more words about feelings, see feelings and emotions vocabulary.

Idioms about time

Idiom	Meaning	Example
once in a blue moon	very rarely	I eat fast food once in a blue moon.
in the nick of time	just in time	We arrived in the nick of time.
call it a day	stop working for today	It's 7 p.m. Let's call it a day.
better late than never	it's good that it happened, even late	You finally replied! Better late than never.
around the clock	all day and night	The team worked around the clock.

Idioms about money

Idiom	Meaning	Example
cost an arm and a leg	be very expensive	That phone cost an arm and a leg.
break the bank	cost too much	A short trip won't break the bank.
tighten your belt	spend less money	We need to tighten our belts this month.
on a shoestring	with very little money	They traveled around Europe on a shoestring.

Idioms about communication

Idiom	Meaning	Example
break the ice	start a conversation in an awkward situation	He told a joke to break the ice.
spill the beans	reveal a secret	Come on, spill the beans! Who's the new boss?
on the same page	in agreement, understanding the same thing	Let's make sure we're all on the same page.
beat around the bush	avoid saying something directly	Stop beating around the bush and tell me.
hear it through the grapevine	hear gossip unofficially	I heard it through the grapevine that she's leaving.

"Break the ice" is very useful in small talk.

Idioms about work and effort

Idiom	Meaning	Example
hit the books	study hard	I have to hit the books this weekend.
go the extra mile	do more than expected	She always goes the extra mile for customers.
cut corners	do something badly to save time or money	Don't cut corners on safety.
back to square one	start again from the beginning	The plan failed, so we're back to square one.
the ball is in your court	it is your turn to decide or act	I've made my offer. The ball is in your court.

Good luck and encouragement

• Break a leg! - good luck (especially before a performance)
• Keep your chin up. - stay positive
• Hang in there. - don't give up during a difficult time
• Fingers crossed. - I hope it goes well

How do you use idioms naturally?

1. Use them in informal situations. In academic essays and formal emails, plain English is usually better.
2. Do not change the words. "A piece of pie" does not work. Idioms are fixed.
3. Do not overuse them. One idiom in a conversation sounds natural; five sounds strange.
4. Learn them from real content. Films and series are full of idioms. See learn English with movies and TV series.
5. Check the variety. Some idioms are more British (over the moon) or American (a whole new ball game). See American English expressions.

Common mistakes

Wrong	Right	Note
It's raining dogs and cats.	It's raining cats and dogs.	The word order is fixed
I'm under weather.	I'm under the weather.	Keep the article
The exam was a cake.	The exam was a piece of cake.	Keep the whole idiom
Break a leg! (to someone going to hospital)	Get well soon!	Break a leg is only for good luck before a performance
Word-for-word translation of an idiom from your language	Look for the English equivalent	Most idioms do not translate directly

Quick quiz

Choose the idiom.

1. The exam was very easy. It was ___.
2. I feel a little sick today. I'm ___.
3. We're tired. Let's ___.
4. That watch was very expensive. It ___.
5. I rarely go to the cinema, maybe ___.

Answers: 1. a piece of cake 2. under the weather 3. call it a day 4. cost an arm and a leg 5. once in a blue moon

Idioms are a B1 and B2 skill that makes your English sound more natural. To work on them step by step, explore the B2 English course with Sage the Turtle.

People Also Ask

What is an idiom in English?

An idiom is a fixed expression whose meaning is different from the meaning of its individual words. For example, it's raining cats and dogs means it's raining very heavily.

Do native speakers really use idioms?

Yes, but they use some much more than others. Everyday idioms like piece of cake, under the weather and on the same page are very common, while many old-fashioned idioms are rarely heard.

Should I use idioms in exams like IELTS?

Use them only if they fit the context naturally. A forced or incorrect idiom sounds worse than simple, accurate English, especially in formal writing.

What is the easiest way to learn idioms?

Learn a few at a time with a clear example sentence, group them by topic, and listen for them in films, series and podcasts. Then try using one in your own conversation or writing.

Related Reading

• 30 Everyday Phrasal Verbs
• Common English Slang
• American English Expressions
• Learn English with Movies and TV Series