The Hardest Words to Spell in English, and What Makes Them Hard

Most lists of the hardest words in English are just lists. You read "bureaucracy", wince in recognition, and forget it by lunch, because nothing on the page told you why it is hard. So nothing helps you with the next one.

Hard words are not hard at random. There are only a handful of ways a word can hide its spelling from you, and most of the notorious ones use two or three of them at once. Once you can name the mechanism, you can often see the trap before you step in it.

What follows sorts the hard words by what makes them hard. It runs from the everyday offenders that turn up in office email to the words that have won the national spelling bee, with the reason behind each. It ends with a way to learn any hard word so that it stays learned.

Five ways a word hides its spelling

A word is hard to spell when the sounds you hear do not point clearly to the letters you need. That gap opens in five main ways.

A letter can be written but not pronounced, like the k in "knight". A word can keep the spelling habits of the language it came from, like the French eau in "bureaucracy". A consonant can be doubled, or not, with no difference in sound, like the pairs in "accommodate". A vowel can be too weak to identify, like the middle of "separate". Or nearly everyone can pronounce the word in a way that drops or blurs a letter, like the first r in "February".

The words people dread most tend to stack these traps on top of one another. "Rhythm" is Greek, which gives it an rh and a y doing a vowel's job, and not one of the five usual vowels. "Conscientious" carries the silent sc of "science" and then a run of weak vowels. "Onomatopoeia" ends in a cluster, oeia, that no native English word would ever produce. Taken one trap at a time, each of these becomes much smaller than it looks.

None of this makes English chaotic, whatever its reputation. In a large 1966 study, Paul Hanna and his colleagues found that about half of 17,000 English words could be spelled correctly from their sounds alone, and that most of the rest follow from meaning and history. The words on this page live in that second group. They are hard, but they are hard for reasons, and a reason is much easier to remember than a string of letters.

Silent letters: sounds that faded, letters that were added

Some silent letters used to be spoken. Speakers of Old English pronounced the k in "knight", and gave the gh a throaty sound like the ch in Scottish "loch". Pronunciation shifted over the following centuries, but by then printing had fixed the spelling, so we still write the word roughly as people said it in Chaucer's day. "Gnaw" and "write" carry the same fossils. So does "Wednesday", which is Woden's day; its first d was once sounded.

Other silent letters were never spoken in English at all. In the 1500s and 1600s, scholars who admired Latin began inserting letters to make English words resemble their Latin ancestors. "Dette" became "debt" to echo Latin debitum. "Doute" became "doubt", and "receite" became "receipt". Nobody ever pronounced these letters. They were added to be seen.

A few arrived by mistake. "Island" descends from Old English igland and never had an s, but someone linked it with "isle", which came from Latin and did, and the s moved in. "Ptarmigan", the mountain bird, comes from Scottish Gaelic; its silent p was added by someone who assumed, wrongly, that the word must be Greek. If you want the full tour, there is a guide to silent letters that covers the patterns in detail.

Borrowed spellings

English borrows words freely and often keeps the lender's spelling. In the middle of an English sentence, then, you are sometimes spelling French by the rules of French.

"Bureaucracy" is the classic case, and it becomes easy the moment you split it. It is French "bureau", a desk or office, joined to the Greek ending "-cracy", rule, the same one that appears in "democracy". Bureaucracy is, quite literally, government by desks. The eau is simply how French writes a long o.

Other borrowed troublemakers work the same way. "Liaison", "entrepreneur", "connoisseur", "questionnaire" and "silhouette" all keep French letter patterns that no English speaker would invent. "Fuchsia", the flower and the color, is named after the German botanist Leonhart Fuchs, which explains the chs that nobody pronounces.

And "colonel" may be the strangest word in common use. English took it from French as "coronel", which is why we still say it with an r. Later, scholars respelled it to match the Italian colonnello. The spelling changed. The pronunciation never followed.

Doubles you cannot hear

In English, a doubled consonant usually sounds exactly like a single one. There is no audible difference between one m and two, so the ear offers nothing, and words like "accommodate" become pure guesswork for anyone who does not know where they came from.

The answer is almost always in the word's parts. "Accommodate" is Latin ad plus commodus, fitting; the ad turned into ac before the c, producing the first double, and com produced the second. "Millennium" is mille, a thousand, plus annus, a year, and each part brings its own double. "Occurrence" takes its cc from the Latin prefix ob, which became oc before a c, and its rr from currere, to run.

Then there are the pairs with no satisfying logic. "Embarrass" has two r's and two s's, while its near relation "harass" has only one r. That is why both sit on every list of commonly misspelled words. The post on double letters in the middle of words shows how the common prefixes produce most of the others.

Vowels you cannot hear

Say "separate" at normal speed. The middle vowel is a quick, colorless "uh" that could be any letter at all. This weak sound turns up in unstressed syllables and is called the schwa. It is the most common vowel sound in English, and the source of a huge share of adult spelling mistakes.

The fix is to find a form of the word, or a relative, in which the vowel is clear. "Separate" descends from Latin parare, to prepare, so it has par in the middle. "Definitely" contains "finite", which settles the i. "Conscience" is con plus science, knowledge shared with yourself, and that one is almost a gift once you notice it. The post on the schwa shows how to find the hidden vowel in almost any word.

Words we say one way and spell another

Some words are hard because almost everyone pronounces them in a way that hides a letter. Many people say "Feb-yoo-ary" and so write "Febuary". "Library" often loses its first r in casual speech. "Mischievous" picks up an extra syllable, "mis-CHEE-vee-us", which tempts people to add an extra i, when the word is simply "mischief" with "-ous" on the end. "Pronunciation" drops the o that "pronounce" keeps, and it catches people precisely because they know the verb so well.

For these, the cure is a spelling voice: a deliberately clear, slightly absurd pronunciation that sounds every letter. Feb-ROO-ary. WED-nes-day. It feels silly.

It works, because it gives memory a sound to hang on each letter.

The everyday hard words, with the trap in each

At the top of the bee

At the national spelling bee, the final words come from everywhere, and they are hard for the same five reasons, only concentrated. Spellers may ask for a word's language of origin, and the best of them use the answer to predict letters they have never seen.

Consider "psammophile", an organism that thrives in sand. A speller who hears "SAM-uh-file" and learns the word is Greek can reason that the opening s may well be ps, as in "psychology", and that the f sound is almost certainly ph. That is not memory for one word. It is knowledge of how a whole language writes itself, which is why champions spend so much time on origins; the piece on how to spell a word you have never seen follows their reasoning step by step.

So which word is actually the hardest?

There is no single answer, and the famous candidates are mostly stunts. The longest word in major dictionaries, a 45-letter name for a lung disease caused by fine volcanic dust, was coined in 1935 by Everett Smith of the National Puzzlers' League, largely for the pleasure of its length. It is built entirely from regular Greek and Latin parts. That makes it long, but not especially hard.

A more useful answer is personal. The hardest word in English, for you, is the one you use every week and get wrong every time. For most adults that is not "chiaroscurist". It is "definitely", "separate", "necessary" or "accommodate", the words that turn up in real email, and those are the ones worth fixing first. The list of the hundred words adults misspell most has a memory trick for each.

How to learn a hard word properly

Hard words are learned the same way as easy ones, with one extra step at the start.

First, find the trap. Ask which of the five mechanisms is at work and mark the exact spot. Most hard words have one or two trouble spots, not nine, and knowing where they are shrinks the problem.

Second, find the reason. A good dictionary gives a word's history in a line, and that line often explains the trap completely. A reason is far easier to hold than a sequence of letters.

Third, test yourself instead of rereading. Hear or say the word, write it from memory, then check. In 2006, Henry Roediger and Jeffrey Karpicke showed that recalling material makes it last far longer than studying it again. Repeat the test tomorrow, in a few days and in a week, because spacing is what turns one correct answer into a lasting one.

Spelling.School is built on that loop: it says the word, you type it, it shows which letters went wrong, and it schedules the word for review with spaced repetition. Its tenth level is made of competition words, and you can add any hard word of your own.

Start with five of your own

Do not try to conquer the hardest words in English. Choose five hard words you actually use and actually get wrong, and for each one, write the trap and the reason on a single line. Test yourself on them tomorrow and again in three days. When all five come out right twice in a row, choose five more.

That small, repeated loop will do more for your writing than any list of famous monsters.

Questions people ask

What is the hardest word to spell in English?

There is no single hardest word, because difficulty depends on the speller and on how often the word is needed. Spelling bee winners such as "chiaroscurist" and "psammophile" are extremely hard, but most people never write them. In everyday writing, words like "accommodate", "definitely", "separate" and "conscience" cause the most trouble, because they hide doubled letters or weak vowels that cannot be heard.

Why is bureaucracy so hard to spell?

"Bureaucracy" is hard because it mixes two languages in one word. It joins the French word "bureau", which spells a long o as eau, to the Greek ending "-cracy", meaning rule, as in "democracy". Once you see it as bureau plus cracy, literally rule by desks, the spelling stops looking random.

What makes a word hard to spell?

A word is hard to spell when its sounds do not clearly point to its letters. The five main causes are silent letters, spellings kept from other languages, doubled consonants that sound single, weak vowels in unstressed syllables, and common pronunciations that drop a letter. Many of the hardest words combine two or three of these at once.

What are the hardest spelling bee words?

The words that win national spelling bees are usually rare borrowings that keep the spelling habits of their source language. Recent examples include "autochthonous" from Greek, "appoggiatura" from Italian, "knaidel" from Yiddish and "psammophile" from Greek. Top spellers study the habits of each language so they can predict the letters of a word from its origin.

How do you learn really hard words?

Start by finding the exact spot where the word goes wrong, then look up the word's history or a related word that explains that spot. Next, test yourself by writing the word from memory rather than rereading it, and repeat the test over several days with growing gaps. Understanding the reason and spacing the practice make hard words stick far better than copying them out.

Why does English have silent letters?

Some silent letters were once pronounced, like the k in "knight", and the spelling stayed after the sound disappeared. Others were added in the 1500s and 1600s by scholars who wanted English words to resemble Latin, which is why "debt" has a b. A few, like the s in "island", were added by mistake because someone guessed the word's origin wrongly.

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