Idiom B2

A wolf in sheep's clothing

A dangerous person who pretends to be harmless or friendly

Meaning

A wolf in sheep's clothing is a person who hides a dangerous, dishonest, or harmful nature behind a friendly, harmless, or trustworthy appearance. The phrase warns that someone's pleasant exterior may disguise bad intentions. Literal: a wolf disguised in a sheep's fleece. Figurative: a threatening person pretending to be safe and kind.

Origin & History

The idiom comes from a warning in the Bible (Matthew 7:15), which cautions against false prophets who 'come to you in sheep's clothing, but inwardly they are ravenous wolves'. A similar idea also appears in one of Aesop's fables, in which a wolf wears a sheepskin to sneak among the flock. Both sources made the image widely known across European languages.

Because the wolf is a classic predator and the sheep a classic symbol of harmlessness, the contrast is instantly clear. The idiom is now used in everyday English to describe deceptive people, misleading products, or dangerous ideas presented in an attractive, reassuring form.

Example Sentences

SentenceContext
Be careful with that salesman — he's a wolf in sheep's clothing.Business, deception
The new policy looks generous, but it's a wolf in sheep's clothing.Politics, hidden danger
She seemed so kind, but she turned out to be a wolf in sheep's clothing.Relationships, betrayal
That loan offer is a wolf in sheep's clothing, full of hidden fees.Finance, scams

How to Use It

The idiom is used as a noun phrase, usually after the verb 'be' or 'turn out to be': he is a wolf in sheep's clothing. Note the apostrophe in 'sheep's' (the clothing belongs to the sheep). It is neutral to slightly literary and works well as a warning about people, organisations, products, or proposals that seem safe but are not.

Common Mistakes

Mistakes to Avoid

He is a wolf in sheeps clothing.

He is a wolf in sheep's clothing. — Use the possessive apostrophe: 'sheep's clothing'.

She is a sheep in wolf's clothing because she is so dangerous.

She is a wolf in sheep's clothing because she is so dangerous. — The dangerous one is the wolf; do not reverse the animals.

That harmless puppy is a wolf in sheep's clothing.

That charming con artist is a wolf in sheep's clothing. — The idiom describes a hidden threat, so the subject must actually be dangerous or dishonest.

Similar Idioms

Cry wolf Pull the wool over your eyes Take it with a grain of salt All Idioms →

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Frequently Asked Questions

What does "a wolf in sheep\u0027s clothing" mean?
"A wolf in sheep\u0027s clothing" is a person who appears harmless, friendly, or trustworthy but is actually dangerous, dishonest, or harmful. It warns that a pleasant exterior may hide bad intentions.
Where does "a wolf in sheep\u0027s clothing" come from?
It comes from a warning in the Bible (Matthew 7:15) about false prophets who come in "sheep\u0027s clothing" but are "ravenous wolves" inside. A similar idea appears in one of Aesop\u0027s fables, making the image widely known.
Can you give an example of "a wolf in sheep\u0027s clothing" in a sentence?
"Be careful with that salesman — he\u0027s a wolf in sheep\u0027s clothing." Another: "The new policy looks generous, but it\u0027s a wolf in sheep\u0027s clothing."
Is "a wolf in sheep\u0027s clothing" formal or informal?
It is neutral and slightly literary. It is acceptable in journalism, speeches, and conversation, and it carries a serious, cautionary tone. It is too vivid for strictly formal academic writing.
What CEFR level is "a wolf in sheep\u0027s clothing"?
B2. Learners need to understand the contrast between predator and prey and the idea of disguise, so it suits upper-intermediate and advanced students.
Why is there an apostrophe in "sheep\u0027s"?
Because the clothing belongs to the sheep — it is the sheep\u0027s clothing. The possessive apostrophe is part of the fixed phrase, so always write "sheep\u0027s clothing".
What are common mistakes with "a wolf in sheep\u0027s clothing"?
Omitting the apostrophe, reversing the animals to "a sheep in wolf\u0027s clothing", and using it for something genuinely harmless. The dangerous one is always the disguised wolf.
What idioms are similar to "a wolf in sheep\u0027s clothing"?
Similar expressions include "not all that glitters is gold", "a snake in the grass", "pull the wool over your eyes", and "cry wolf". The closest in meaning is "a snake in the grass".
Can "a wolf in sheep\u0027s clothing" be used in writing?
Yes, in journalism, opinion pieces, reviews, and speeches as a warning about deceptive people, products, or proposals. In strictly formal academic writing, use "deceptive" or "deliberately misleading" instead.
How do I practise idioms like "a wolf in sheep\u0027s clothing"?
Use LexFizz Flash Cards and Flip Tiles, and describe a misleading offer or character — "that deal is a wolf in sheep\u0027s clothing" — to make the idiom memorable.