The Longest Word in English

Last week I was teaching pronunciation to my class. We were looking at how the stress in a word changes depending on its grammatical form and the number of syllables it has. We looked at two, three, four and five syllable words and practised together. Just as we were about to take a break, one of my students asked "What is the longest word in English?".

Now, that's a very good question. After doing some research here, I found that the longest word in English is (deep breath...) Pneumonoultramicroscopicsilicovolcanoconiosis, a lung disease caused by breathing in the dust produced by a volcano.  It's 45 letters long and absolutely useless to know.  Although this word appears in one or two dictionaries, I wouldn't describe it as a common word, or even a real word. It's a scientific term and one which is hardly used at all.

When I was at school, we were taught that the longest word in English is antidisestablishmentarianism (28 letters) and to many people, this is still considered to be true. Why? Because it has a meaning.  To understand this, we need to look at how it is formed and the rules of affixation that dictate how we make words in English.

Let's start with the key part of the word, establishment. The establishment is the existing power structure with in a country. In the UK, we could say that this includes the government, and to a lesser extent the monarchy and the church.

Now let's look at the prefixes. Anti- means opposite or against something whereas dis- is used to mean a negative or reversing force or idea. For example, antismoking and disappear. So, antidis- means to be against a negative force or idea. Although it's not common to have two prefixes at the beginning of a word, it is still grammatically correct.  Are you keeping up so far?

At the end of the word we find the suffixes. While prefixes change the meaning or a word, suffixes change its grammar. In our word we have two suffixes, -arian and -ism. The first is a way of personalising a noun, as in librarian (a person who works in a library). The second is a way of creating a noun from a verb as in criticism (from the verb to criticise). So, -arianism means the beliefs and practices of a group of people, such as vegetarianism.

Right, let's put it all together: anti-dis-establishment-arian-ism means the belief (arianism) which opposes (anti) removing (dis) the power of church and state (establishment).

Phew! For the record, that's twelve syllables with the stress on the ar of -arianism. It's also a real word, as it follows the rules of affixation and word formation. It's not however, a word which is used very often as I'm sure you can imagine.

I said at the beginning of the post that this word came up when I was teaching pronunciation. Well, the lesson quickly diverted into word formation, but to bring it back to the original topic, and to put my money where my mouth was, I offered £5 to any student who could correctly pronounce the word. A number of students tried, and although a couple came very close, the money is still safely in my pocket. Now what does that say about my teaching?

Thanks for reading.

By Andy


syllable - (n.) a separate sound within a word e.g. sil-uh-bull

considered - (v.) to be believed by someone

affixation - (n.) the act of adding prefixes and suffixes to words

to a lesser extent - (fixed expression) not as strongly or importantly

monarchy - (n.) the Royal Family 

prefixes - (n.) parts of words placed at the beginning of a word

keep up - (phr.v.) to be at the same level as everyone else (here it means to understand)

suffixes - (n.) parts of words placed at the end of a word

practices - (n.) habits or customs

phew - (interjection) used to express disgust, exhaustion or surprise

for the record - (fixed expression) used before giving facts, often to correct what is known or said

come up - (phr.v.) to take place or occur at a certain point

diverted - (v.) moved in a direction which was not originally planned

to put your money where your mouth is - (idiom) to support something you believe in, usually by offering money 

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