Learn 11 spooky English idioms for Halloween, from skeletons in the closet to cold feet. Plain meanings, everyday examples and tips to use them well.
Halloween is on Saturday, October 31. Pumpkins are out on the porches, and kids are planning their costumes. It is also a good week to learn a few idioms. English has many expressions about devils, ghosts, blood and the night, and Canadians use them all year: at work, at home and with the neighbours. Don't worry, none of them are really scary. Most are about everyday feelings, like being nervous, being angry or saying no.
Why this matters for the CELPIP test: in Writing and Speaking, vocabulary is one of the four things raters score, and tone counts too (CELPIP Performance Standards). An idiom used in the right place sounds natural. An idiom used in the wrong place sounds strange. A plain word used correctly is always safer, so learn the meaning and the tone first, and use an idiom only when it fits.
Devils and skeletons
1. Speak of the devil
Meaning: You say this when a person walks in just as you are talking about them. It is friendly. You are not calling anyone a devil.
Example: "Has anyone seen Priya's report? Oh, speak of the devil, here she is!"
Where it comes from: It is short for an old saying, "speak of the devil and he will appear." People once believed that saying the devil's name could call him.
Tip: This one is for speaking, not writing. In a Speaking answer about a personal experience, it can bring a short story about a coworker or a friend to life. In a formal email, leave it out.
Hear it in real videos: YouTube clips with "speak of the devil"
2. Skeletons in the closet
Meaning: A secret from someone's past that they would not like other people to know, often something embarrassing.
Example: "Every family has a few skeletons in the closet. Ours is Uncle Mike's short career as a wedding singer."
Tip: You can say one skeleton too: "He has a skeleton in his closet." In British English you may hear "a skeleton in the cupboard", but in Canada people say "closet".
Hear it in real videos: YouTube clips with "skeletons in the closet"
3. The devil is in the details
Meaning: A plan can look simple, but the small details can cause big problems. So check them carefully.
Example: "The new lease looks fine, but the devil is in the details. Read the part about who pays for repairs before you sign."
Where it comes from: It probably grew from an older saying, "God is in the details", which means that small details matter.
Tip: This idiom is neutral, not slang, so it can fit a semi-formal email or a Writing survey answer. For example, use it when you explain why the other option has hidden problems.
Hear it in real videos: YouTube clips with "devil is in the details"
4. Play devil's advocate
Meaning: To argue for the other side, even if you do not really believe it, to test an idea.
Example: "I like the idea of a four-day work week too, but let me play devil's advocate: who answers the phones on Fridays?"
Where it comes from: The Catholic Church once had an official whose job was to argue against making a person a saint, so that every weak point was checked. People called him "the devil's advocate".
Tip: "Let me play devil's advocate" is a polite way to disagree in a meeting or a discussion. It tells people you are testing the idea, not attacking them.
Hear it in real videos: YouTube clips with "play devil's advocate"
Fear and nerves
5. Get cold feet
Meaning: To feel nervous just before something important, and maybe change your mind.
Example: "We were ready to sign the lease for the bigger apartment, but my husband got cold feet when he saw the rent."
Tip: A story about a personal experience often has a moment of doubt. "I almost got cold feet, but in the end I went" is a natural way to tell it. Say "cold feet", never "a cold foot".
Hear it in real videos: YouTube clips with "get cold feet"
6. Freak out
Meaning: To suddenly become very upset, scared or excited. This is a phrasal verb, not an idiom, but you will hear it a lot around Halloween.
Example: "The haunted house at the community centre freaked my kids out, but they want to go again next year."
Tip: It is informal. It is fine with friends and family, but in an email to a landlord or a manager, say "I was very worried" instead.
Hear it in real videos: YouTube clips with "freak out"
7. Make your blood boil
Meaning: To make you very angry.
Example: "It makes my blood boil when people block my driveway."
Where it comes from: It comes from an old idea that anger heats the blood.
Tip: This is a strong phrase. In a complaint to a company, calmer words work better: "I was very disappointed" sounds more professional than "It made my blood boil."
Hear it in real videos: YouTube clips with "make one's blood boil"
Dead serious
8. Over my dead body
Meaning: Absolutely not. You will never allow it. People often say it with a smile.
Example: "My teenage son wants to paint his bedroom black. Over my dead body!"
Tip: It is very strong and informal, so keep it for family and friends.
Hear it in real videos: YouTube clips with "over my dead body"
9. Wouldn't be caught dead
Meaning: You would never do, wear or go somewhere, because you think it is embarrassing.
Example: "My dad said he wouldn't be caught dead in a costume, but this year he came to the party dressed as a pumpkin."
Tip: After it, use a place, a piece of clothing or an -ing verb: "in a costume", "at that mall", "wearing that hat".
Hear it in real videos: YouTube clips with "wouldn't be caught dead"
Night and the moon
10. Graveyard shift
Meaning: Work during the night, usually from around midnight to the early morning.
Example: "My neighbour works the graveyard shift at the hospital, so we keep the music down in the afternoon."
Where it comes from: No one is sure. One idea is that the streets are as quiet as a graveyard at that time of night.
Tip: This is a real workplace term, not just a joke. It is useful when you talk about jobs, schedules or a busy family week.
Hear it in real videos: YouTube clips with "graveyard shift"
11. Once in a blue moon
Meaning: Very rarely.
Example: "My landlord answers emails once in a blue moon, so I usually call him."
Where it comes from: Today a "blue moon" often means a second full moon in one calendar month. That does not happen often, and the moon does not usually look blue.
Tip: It is a nice change from "rarely" or "almost never" when you talk about your habits.
Hear it in real videos: YouTube clips with "once in a blue moon"
Quick summary
| Idiom | Meaning | Tone |
|---|---|---|
| Speak of the devil | The person we were talking about just arrived | Informal |
| Skeletons in the closet | Secrets from the past | Informal |
| The devil is in the details | Small details can cause big problems | Neutral |
| Play devil's advocate | Argue the other side to test an idea | Neutral |
| Get cold feet | Feel nervous just before something important | Informal |
| Freak out | Suddenly become very upset, scared or excited | Informal |
| Make your blood boil | Make you very angry | Informal |
| Over my dead body | Absolutely not | Informal |
| Wouldn't be caught dead | Would never do or wear something | Informal |
| Graveyard shift | Night work | Neutral |
| Once in a blue moon | Very rarely | Informal |
How to use these idioms well
- One is enough. One idiom that fits sounds natural. Five in one answer sound forced.
- Match the tone. Informal idioms are for friends and family. With a manager, a landlord or a company, choose neutral ones like "the devil is in the details", or plain words.
- Keep the exact form. Idioms do not like changes: it is "cold feet", "blood boil" and "blue moon", not "cold foot", "blood cooks" or "a moon that is blue".
- When in doubt, leave it out. A plain word used correctly is better than an idiom used wrongly.
Keep practising
Every idiom above has its own page with more examples, and its video link shows it in real YouTube clips. You can browse all of them on our idioms page, then test yourself in the idiom word game (it needs a free account). Happy Halloween, and if someone walks in while you are practising, you know what to say: speak of the devil!
