Ever walked past a conversation and caught a few words that sounded like English, or French, or Spanish, but felt like they were from another planet? You might have brushed up against a “shadow tongue”—an anti-language. These aren’t just collections of slang; they are intricate linguistic systems forged in the margins of society, designed to be a shield, a secret handshake, and a badge of identity all at once. From the coded speech of prisoners to the defiant cant of persecuted groups, anti-languages are a testament to the power of language to create a world within a world.

But how do these secret lexicons work? What linguistic tricks do they use to remain opaque to outsiders while being perfectly clear to insiders? And how on earth do linguists even begin to decipher codes that were specifically designed to keep them out?

What Exactly Is an Anti-Language?

The term was coined by the influential linguist M.A.K. Halliday, who saw these linguistic forms as more than just secret codes. He described an anti-language as the tongue of an “anti-society”—a subculture that exists in opposition to the mainstream. Think of criminal gangs, prisoners, revolutionary groups, or communities ostracized for their identity.

The primary purpose of an anti-language is to create and reinforce a social boundary. If you understand it, you’re one of us. If you don’t, you’re one of them. This is what separates it from simple jargon or slang.

• Jargon is specialized vocabulary used for precision within a profession (e.g., medical or legal terms). Its goal is clarity, not exclusion.
• Slang is often about novelty, informality, and expressing a shared, casual identity. While it can exclude older generations, its secrets are usually short-lived.
• An anti-language, however, is a conscious act of linguistic rebellion. It creates an alternate reality with its own values by systematically re-naming the world. In an anti-language, a “policeman” isn’t just a “cop”; he might be a “pig”, a “screw”, or a “bogey”—terms loaded with the subculture’s worldview.

The Building Blocks: How Shadow Tongues Are Forged

You can’t just invent a new language from scratch. It’s too difficult and inefficient. Instead, anti-languages cleverly piggyback on the grammar of the dominant language they exist within. A speaker of Polari still uses English grammar, and a speaker of Verlan uses French grammar. The true magic happens at the word level, a process linguists call relexicalization—systematically replacing the vocabulary.

This replacement happens through several common, creative methods seen across the globe:

1. Metaphor and Imagery: Words are given new meanings based on a visual or functional similarity. A prison guard turns the key, so he becomes a “screw”. Money is “bread” because it’s a fundamental necessity.

2. Borrowing from Other Languages: Subcultures often borrow words from other marginalized groups or foreign languages. English thieves’ cant, for example, is famously peppered with words from Romani (the language of the Romany people) and Yiddish. This adds another layer of obscurity.

3. Wordplay and Reversal: This is a classic technique. The most famous modern example is French Verlan, which works by inverting syllables. The word l’envers (meaning “the reverse”) becomes verlan. A woman (femme) becomes a meuf; a crazy person (fou) becomes an ouf. A similar, older English tradition is backslang, where “boy” becomes “yob”.

4. Abbreviation and Compounding: Shortening words or smashing them together is another quick way to create new vocabulary that is unintelligible at speed.

By using the existing grammar but swapping out the key nouns, verbs, and adjectives, an anti-language becomes a riddle spoken in plain sight. You can hear the rhythm and flow of your own language, but the meaning remains tantalizingly out of reach.

A Global Tour of Anti-Languages

These principles aren’t theoretical; they are spoken on the streets, in prisons, and in hidden communities worldwide.

Polari: The Lost Language of Gay Britain

In the UK, before the decriminalization of homosexuality in 1967, men used Polari to communicate without risking arrest. It was a fabulous, witty, and life-saving anti-language. Its vocabulary was a magpie’s nest of sources: Italian (“bona” for good), thieves’ cant (“naff” for bad/tacky), rhyming slang (“zhoosh” for a haircut), and backslang (“riah” for hair). To “vada the dolly eek” was to look at the pretty face—a phrase that could be safely spoken in a pub, its meaning floating right over the heads of potentially hostile listeners.

Lunfardo: The Soul of a Tango

In the late 19th-century slums of Buenos Aires, a mix of Italian immigrants, criminals, and the urban poor created Lunfardo. It began as a prison cant but soon infused the city’s culture, most notably through the lyrics of tango music. It used Italian words, reversed syllables (like Verlan), and created its own rich vocabulary. While many Lunfardo words are now part of standard Argentinian slang, its origins lie firmly in the anti-language of the underworld.

Grypsera: The Code of the Polish Prison

This is a classic prison anti-language from Poland, used by inmates (grypserzy) to distinguish themselves from outsiders and guards. It has its own code of ethics and is a crucial part of the prison hierarchy. Understanding and speaking Grypsera is a mark of being a trusted, seasoned inmate. Not knowing it marks you as a sucker (frajer). Its vocabulary is built around the realities of prison life, with specific words for types of inmates, guards, actions, and objects.

The Linguist as Detective: Studying the Unspoken

This all raises a key question: if anti-languages are designed to be secret, how do we know so much about them? Studying them is one of the most challenging tasks in linguistics, requiring the skills of a detective and an ethnographer.

Linguists face the classic Observer’s Paradox: the moment a community knows it is being studied by an outsider, it may stop using its secret language altogether. Trust is paramount. Researchers often rely on:

• Archival Records: Court transcripts, police reports, and old newspaper articles sometimes inadvertently document criminal cants.
• Cultural Artifacts: Song lyrics (like Tango for Lunfardo) or underground literature can preserve the vocabulary of an anti-language long after it has faded from active use.
• Informants: The most valuable resource is an informant—a member of the community willing to share the secrets of their language. This requires building genuine, long-term relationships based on mutual respect. The linguist is no longer just an observer but a confidant.

Anti-languages are far more than a linguistic curiosity. They are a powerful reminder that language is not just for communication, but for survival, rebellion, and the creation of community. Wherever there is a society, there will be an anti-society at its edges, and wherever there is an anti-society, it will whisper, sing, and shout in its own shadow tongue.