How the Cassidy-JLU writing system spells Jamaican Patois

Cassidy/JLU is a phonemic writing system for Jamaican Patois: one sound is always written one way, and one written form always says one sound. It was devised by the linguist Frederic Cassidy and later codified by the Jamaican Language Unit at the University of the West Indies, Mona. It uses thirty-eight graphemes, has no c, no q and no x, and once you know them you can say a word you have never seen before straight off the page, without having heard anybody say it.

The one principle the whole system rests on

Almost everything below is a consequence of a single rule, so it is worth stating it in both directions before anything else.

One phoneme, one grapheme. One grapheme, one phoneme. Every distinct sound in the language has exactly one written form, and every written form says exactly that one sound, everywhere it appears, in every word, with no exceptions to memorise.

English does not work like this and neither does the popular spelling of Patois that borrows from it. In English, ough is read at least six different ways, and the k sound of cat is written c, k, ck, ch and qu depending on the word — cat, kite, back, chorus, mosque. Every one of those is a fact you have to be told. A phonemic system has no such facts. There is nothing to be told beyond the inventory itself.

Three things follow, and they are the entire value of the system.

You can read aloud a word you have never met. Decode the graphemes left to right, say what they say, and you have said the word. You can write down a word you have only ever heard, and another reader will pronounce it back the way you said it. And a machine can do both, which is why this site stores a Cassidy/JLU form beside every phrase: a program can turn that string into a sequence of sounds by rule, with no pronunciation dictionary, and then line it up against a recording of your voice.

The last one is not a footnote. Without it, teaching pronunciation would mean building a pronunciation dictionary for the language from scratch, and that is the sort of cost that decides whether a small product can teach pronunciation at all.

Who made it, and who keeps it

Frederic Cassidy was a Jamaican-born linguist, and the spelling conventions on this page originate with his work on Jamaican speech in the 1960s. They were later codified into the teachable form in use today by the Jamaican Language Unit at the University of the West Indies, Mona, which has published guidance on writing Patois in the system.

We follow that published system. We have no partnership with the Jamaican Language Unit, nothing here is endorsed by it, and nothing on this page should be read as speaking for it. The conventions are a writing system; this page is our own description of them.

The vowels

Twelve of the thirty-eight graphemes are vowels: five short, three long, four diphthongs. This is where a reader coming from English has the most to unlearn, because English vowel spelling is where English is least reliable.

The five short vowels

Grapheme	Roughly as in	Example
a	the a of father, shortened	dat — that
e	the e of bed	dem — they, them
i	the i of sit	di — the
o	the o of hot	moch — much
u	the u of put	gud — good

Each is one letter and each says one thing. No letter in the system is silent, and outside the two-letter graphemes set out below, no letter changes the sound of the letter beside it. A written vowel always corresponds to a vowel you can hear.

The three long vowels, and why length is not decoration

Length is contrastive in Patois: holding a vowel longer can change the word, not merely the delivery. So the system writes length by doubling the letter, and never leaves it to be inferred.

Grapheme	Example	English
aa	taak	talk
ii	siit	seat
uu	muun	moon

The pair that makes this concrete is siit against sit. They differ in exactly one respect — how long the vowel is held — and they are two different words. Write sit when you meant siit and you have not written a variant spelling; you have written a different word. The same care is owed to aa and uu: shorten the vowel in taak and you have not written a variant of taak, you have written a different sequence of sounds.

This is the slip an English reader makes most often when first writing in the system. English does not use doubling for length in any consistent way — its ee and oo are separate vowel qualities rather than long versions of e and o — so the instinct to tidy ii down to a single i is very strong. Resist it.

The four diphthongs

A diphthong is one vowel that moves while you say it. Patois has four, each written as two letters that are read as a single unit.

Grapheme	Example	English	Note
ie	niem	name	The vowel English writes ay
uo	guo	go	The vowel English writes oh
ai	jrai	dry
ou	nou	now

These four are where the system looks most alien, and ie is the worst offender. The word for the period between one night and the next is die — three letters that spell an entirely different word in English. It is not a joke at the reader's expense; it is what falls out of writing that vowel the same way in every word it appears in. name(niem) and day(die) carry the same vowel, so they carry the same two letters, and a system that made an exception for one of them would stop being a system.

The nasal mark

One grapheme is neither a vowel nor a consonant. hn is written after the vowel it nasalises, and it marks the vowel as nasal rather than adding a sound of its own.

It is the easiest mark to leave out and the most expensive one to lose, because at least one pair in everyday use is separated by it. kyan(kyan)— can has a short vowel and no nasal. cyaahn(kyaahn)— cannot has a long vowel and the nasal mark. They are opposites. Leave either mark out of the second and it stops saying cannot — and nothing in the string will look odd, so nothing warns you that you have written the reverse of what you meant.

That is the general shape of the argument for marking everything the ear distinguishes. A phonemic system has no redundancy to spare: every mark in it is doing work, so any mark you leave out is information the reader does not get back.

The consonants, and the three palatalised sequences

The consonants are the least surprising part of the system, and most of them do what an English reader expects.

Class	Graphemes
Stops	p b t d k g
Affricates	ch j
Fricatives	f v s z sh zh h
Nasals	m n ng
Approximants	l r w y
Palatalised	ky gy ny

Four of these repay attention. ch and j are the sounds at the start of English church and judge. They occur where an English reader expects them, and also where English has a t or a d before an r — so tree(chrii)— three and drink(jringk). zh is the sound in the middle of English measure, which English has never given a written form of its own; here it has one, as in mezha and vizhan. And ng is one grapheme for the sound at the end of English sing, never an n followed by a g.

The three palatalised sequences — ky, gy and ny — are written as units because they behave as units. They are a consonant with a y-glide fused onto it, and they are among the most recognisable sounds in Jamaican speech: gyal(gyal), car(kyar), nyam(nyam)— to eat. English spelling has no settled way to write any of them, which is one of the clearer demonstrations that borrowed spelling was never going to be sufficient.

Two consonants also carry a syllable on their own, with no vowel written beside them, because there is no vowel there to write. likl ends in a syllabic l and notn in a syllabic n. Both are two syllables. Popular spelling writes them likkle and nutten and adds vowels the mouth does not make.

The three letters the system does not use

There is no c, no q and no x in Cassidy/JLU, and their absence is deliberate rather than accidental.

c is the clearest case. In English it says the sound of k in cat and the sound of s in city, which is precisely the ambiguity a phonemic system exists to remove. Both of those sounds already have unambiguous letters, so c has nothing left to do. q is redundant in the same way: in English it almost always spells a k followed by a w, and both of those letters are already available. x is two sounds wearing one letter.

The practical consequence catches out most people writing their first phonemic form: a c you were about to write becomes a k, or an s where it was saying the sound it has in city. The everyday spellings Everyting criss and cyaahn become evriting kris and kyaahn. Neither everyday form is a mistake — they are simply written in the other system, where c is a perfectly ordinary letter.

Nor are there digits, capital letters or punctuation. The system is lowercase throughout, because case carries no sound; spaces separate words and nothing else appears between them.

How to read a word: longest match wins

Because some graphemes are two letters long, reading requires one rule, and it is the same rule a computer applies.

Take the longest grapheme that matches, left to right, and never look back. In siit, the ii is one grapheme and is never read as two separate i sounds. In jringk, the ng is one grapheme, not an n followed by a g. In nyam, ny is taken as a unit before the y is considered on its own.

Applied consistently, this rule reads every word in the system correctly, and it is worth practising as a mechanical habit: run your eye along the word, take the biggest bite available at each step, and say what you took. That is the whole reading procedure. There is no second stage where you check the word against a list of exceptions, because there is no list.

Read this passage yourself

The test of a writing system is whether somebody who has just met it can use it. Do not read ahead to the table; try these five first, out loud.

we yu de pan — mi de ya — mi suun kom — likl muor — waak gud

Work along the first one. w, e — one syllable, the vowel of bed. y, u — the vowel of put. d, e again. p, a, n. Four short vowels, no long ones, no diphthongs, and you have said a question you have almost certainly heard before.

The fourth is the one that rewards care. likl has four letters and two syllables: l, i, k, and then an l carrying its own syllable with no vowel written for it. muor is m, then the diphthong uo taken as one unit by the longest-match rule, then r. Read the u and the o as two separate vowels and you have two syllables where the language has one.

The five lines, in both spellings

Patois	Written (Cassidy)	English	Word for word
Weh yuh deh pon?	we yu de pan	What are you up to?	where you there on
Mi deh yah	mi de ya	I am here	I there here
Mi soon come	mi suun kom	I will be back shortly
Likkle more	likl muor	See you later	little more
Walk gud	waak gud	Take care	walk good

If you got four of the five close, the system has done its job. Nothing there was memorised. You decoded it.

What the system does not tell you

It is worth being precise about the system's limits, because a notation that seems to answer everything invites the reader to ask it questions it cannot hear.

It does not tell you who says it this way. Jamaican speech runs along a range, from the deepest creole to something very close to English, and speakers move along that range constantly according to who they are talking to. A phonemic form records one pronunciation faithfully; it says nothing about where on that range the speaker was standing. That subject has its own guide, on the Jamaican Patois continuum.

It does not tell you grammar. The system spells words, and the words it spells include the little grammatical markers that do the heavy lifting in Patois — the ones that mark tense and aspect as separate words rather than as endings. Each of them has a fixed spelling, which makes them easy to spot once you know them, but knowing how to write did and a is not the same as knowing when to use them. Their work is set out in our guide to Patois verb tenses.

And it does not tell you meaning. A phonemic form is a pronunciation, nothing more. That is why every phrase on this site carries an English sense beside the two spellings.

Nor does it write stress or intonation. All thirty-eight graphemes describe the sounds of a word; none of them marks which syllable is leaned on or how the pitch moves across a sentence, and the tune of a sentence is a large part of what makes Patois sound like itself. That part comes from listening, which is why a recording sits beside the spelling rather than instead of it.

Nobody is obliged to write this way

This matters more than anything else on the page, so it goes last where it will be remembered.

The everyday, English-based spelling that Jamaicans write to each other is not wrong, is not careless, and is not a rough draft of this system. It does a different job — it is built for instant recognition by somebody who already reads English and already speaks Patois, and at that job it beats Cassidy/JLU comfortably. Those two systems answer two different questions, and the reasons behind each are set out in our guide to why Patois is spelled two different ways.

Write to your reader. In a message to your family, write the way your family writes. Reach for the phonemic form when the question is specifically pronunciation: when you want to know how a word sounds, when you want to record how it sounds, or when you want to compare two words that the everyday spelling makes look identical. That is why this site shows both, side by side, on every phrase — and why the grammar route through the language, at how to speak Jamaican Patois, never asks you to choose between them.