Friendships, partnerships, and bonds that feel unbreakable often leave us reaching for the perfect phrase to describe them. One of the most vivid idioms in English that captures this closeness is “as thick as thieves.” It’s a saying rich with history, layers of meaning, and a fascinating journey from the 18th-century underworld of England and France to modern conversations, literature, and media. As Thick as Thieves.
In this article, we’ll break down the meaning, origin, and usage of the idiom as thick as thieves, exploring both its positive and negative connotations, showing examples from everyday speech, classic novels, journalism, and politics, and even comparing it with synonyms. Along the way, you’ll discover how this proverb has stood the test of time and why it remains so powerful in describing relationships built on trust, secrecy, or complicity.
What Does “As Thick as Thieves” Mean?
The idiom “as thick as thieves” is commonly used to describe two or more people who are extremely close, inseparable, or deeply bonded.
- It suggests intimacy, trust, and the idea that the people involved share secrets or confide in one another.
- The word thick here doesn’t mean “dense” but rather “close-knit” or “intimately connected.”
- Thieves were historically seen as co-conspirators who had to rely on absolute loyalty to succeed, making the phrase a perfect metaphor for strong relationships.
Quick Definition:
To be as thick as thieves means to be very close friends who trust and support each other, often in a way that seems secretive or exclusive.
Read More: Is It Correct to Say “More Easy”? A Complete Grammar Guide
Origin and Etymology of the Phrase
The phrase dates back to the 18th century, though earlier roots can be traced to French sayings like s’entendre comme larrons en foire (“to get along like thieves at a fair”).
- Richard Twining, in his memoirs (1791), is one of the first to record the phrase in English.
- By the early 1800s, the idiom was appearing in literature, newspapers, and conversations in London.
- The criminal underworld of the 18th and 19th centuries helped cement the expression in English, where thieves depended on secrecy and loyalty.
Timeline Snapshot
| Period | Development |
| 1699 | Early references in English dictionaries of slang (canting crew). |
| 18th century | French phrase larrons en foire popular in Europe. |
| 1791 | Richard Twining records as thick as thieves in his memoir. |
| Early 1800s | Widely used in England, especially London. |
| 1833 | Appears in Theodore Hook’s The Parson’s Daughter. |
| 20th century | Spread globally through media, novels, and journalism. |
| Today | Used in both formal and informal contexts to describe close ties. |
The metaphorical power of the phrase lies in the image of thieves: secretive, loyal, and united—bound by necessity and trust.
Positive and Negative Connotations
The idiom has a dual personality. Depending on the context, it can highlight either deep friendship or suspicious alliances.
| Context | Connotation | Example |
| Positive | Strong friendship, intimacy, or loyalty. | “Sarah and her sister are as thick as thieves. They share everything.” |
| Negative | Shady dealings, conspiracies, or unethical cooperation. | “Those corrupt politicians are as thick as thieves, milking government funds.” |
This flexibility makes the idiom versatile in literature, journalism, and everyday talk.
Everyday Examples of “As Thick as Thieves”
- Friendship: “John and James have been as thick as thieves since kindergarten.”
- Family Bond: “Despite living in different cities, Sarah and her cousin are still as thick as thieves.”
- Workplace Alliance: “The two colleagues are as thick as thieves, always planning strategies together.”
- Shady Context: “Reporters uncovered evidence that the doormen and smugglers were as thick as thieves.”
Synonyms and Related Expressions
The English language is full of idioms that capture closeness or secrecy. Here’s how as thick as thieves compares:
| Idiom / Phrase | Similarity | Usage Example |
| Two peas in a pod | Close friendship, similarity. | “They’re like two peas in a pod, always together.” |
| Joined at the hip | Inseparable physically and emotionally. | “The twins were practically joined at the hip.” |
| Bosom buddies | Deep, trusted friends. | “They’ve been bosom buddies since college.” |
| In cahoots | Secretive alliance, usually negative. | “The businessmen were in cahoots to fix the deal.” |
| Best mates / BFFs | Informal, modern friendship term. | “We’ve been best mates for years.” |
Usage in Literature and Media
The idiom has appeared in countless works, reinforcing its popularity.
- J.D. Salinger – The Catcher in the Rye
Holden and his sister Phoebe are as thick as thieves, bound by a strong sibling connection. - Harper Lee – To Kill a Mockingbird
Scout and Dill’s summer adventures portray them as thick as thieves. - F. Scott Fitzgerald – The Great Gatsby
Tom Buchanan and Myrtle’s affair is an example of being as thick as thieves in secrecy. - Modern Media
Political journalists often describe alliances between leaders as being “as thick as thieves,” especially when secrecy or backroom deals are implied.
Real-Life Situations
The idiom isn’t limited to books. It shows up in everyday life:
- Friendships: College roommates who share secrets.
- Work Relationships: Journalists collaborating on an investigation.
- Family Bonds: Parent-child relationships built on deep trust.
- Shady Deals: Criminal gangs protecting their own interests.
Grammar and Usage Notes
- Part of Speech: Idiom (used as a predicate phrase).
- Register: Common in informal spoken English, though occasionally used in formal writing for effect.
- Structure: Typically follows the verb be: “They are as thick as thieves.”
- Variations: Sometimes shortened to “thick as thieves.”
Tip for Learners:
Don’t confuse thick here with “not smart.” In this idiom, thick = close, intimate, strong in bond.
Cultural and Global Perspective
- In French, the idiom s’entendre comme larrons en foire carries the same meaning.
- In American English, the phrase became especially popular in the 1830s and 1960s, often tied to political scandals and shady alliances.
- Across literature, sports, espionage tales, and even TV shows, the idiom keeps surfacing to describe relationships that feel intense, loyal, or suspiciously close.
FAQs
Q1: Is “as thick as thieves” positive or negative?
It can be both. Positive in friendships and family ties, negative in shady or corrupt dealings.
Q2: What’s the origin of the idiom?
It comes from 18th-century England, influenced by the French saying larrons en foire.
Q3: Can I use this idiom in formal writing?
Yes, but sparingly. It’s more natural in conversation, storytelling, or journalism.
Q4: What are some synonyms?
“Two peas in a pod,” “joined at the hip,” “bosom buddies,” “in cahoots,” and “best mates.”
Q5: Is the word thick negative in this idiom?
No. Here, thick means close-knit or intimate, not unintelligent.
Conclusion
The idiom “as thick as thieves” has traveled a long road from 18th-century slang to a modern English expression that captures both the beauty of friendship and the shadow of secrecy. Whether you’re describing inseparable childhood friends, siblings who share everything, or politicians bound by shady deals, the phrase adds vivid color and depth.
At its core, the expression reminds us of the power of trust, intimacy, and loyalty—whether used to highlight the good or the bad. In life’s ups and downs, having someone who’s as thick as thieves with you is both a comfort and a bond worth cherishing.
