What Is the Longest Word in English?

Have you ever wondered what the longest English word in the world is? Or how many letters does such a word contain? The identity of the longest word in English language could differ by defining a word differently. It could be a notable long word like a place name/personal name or creations of long words such as a coinage/technical term.

What is the Longest Word in the English Language?

What is the longest word in the world? Long words consisting of hundreds of thousands of letters only exist in alphabetic languages like English. For character-based languages like Chinese, a word is made up of one or a few characters, making their length notably limited. 


The length of the English word is most commonly based on orthography and the total number of its written letters. There’s no definite answer to what the world’s longest word is. To give a particularly vivid example, the word “great-great-great-…great-great-grandparent” contains an arbitrary amount of letters, depending on how many “-great”s are attached to the root word “parent.” In such case, no other English word can beat this word in terms of the counting numbers of the written letters because you can add as many “-great”s as you like to extend the length. 


When it comes to the biggest word in the world by magnitude, the word for the chemical composition of titin (Methionylthreonylthreonylglutaminylalanyl…isoleucine) takes the crown with 189,819 letters. Yes, this long word looks like the text produced by someone who had accidentally sat on the keyboard for a considerable amount of time. If you have three hours to spare and the insane patience, you can try to say the entire word. 

Its incredible length and the controversy over whether it should be considered a word have hindered this technical term for the largest known protein from entering the dictionary. 

The second longest word in English is Methionylglutaminylarginyltyrosylglutamyl…serine with 1,909 letters. Compared to the longest word in English, this chemical term of E coli TrpA (P0A877) is luckier since it is the longest published word in English, though not in a dictionary.

Ten Longest English Words in the Dictionary

The length of a word is measured by the number of its written letters. In the following passage, we will list the ten longest words in the English dictionaries according to their length. Depending on their usage and popularity, these words are listed in one or more of the major dictionaries. 

Forty-five Letters

Pneumonoultramicroscopicsilicovolcanoconiosis, the synonym for the disease silicosis, is the longest word in the most trusted English dictionaries like the Webster’s, Oxford, Chambers, and Random House with 45 letters. This medical term was coined in 1935 and describes the occupational lung disease caused by breathing in crystalline silica dust. Interestingly, this word was purposely designed to invent the then-new longest word. Consequently, the Oxford English Dictionary describes it as a factitious word. 

Thirty-seven Letters

The second longest word in the English dictionary is the 37-letters-long word hepaticocholangiocholecystenterostomies, a surgical term in Gould’s Medical Dictionary that describes it as the creation of a link between a hepatic and the gall bladder and between the gall bladder and the intestine.

Thirty-four Letters

The third longest word published in the English dictionary is supercalifragilisticexpialidocious with 34 letters. It is a song and single by Julie Andrews and Dick Van Dyke from the Disney musical film Mary Poppins in 1964. 

Thirty Letters

The adjective hippopotomonstrosesquipedalian is 30 letters long, ranking fourth on our list of the longest English words in the dictionary. Mrs. Byrne’s Dictionary of Unusual, Obscure and Preposterous Words defines it as of/pertaining to an extremely long word.  

Twenty-nine Letters

The word floccinaucinihilipilification comes fifth with 29 letters. Dating back to 1741, it is the longest word in the 1st edition of the Oxford English Dictionary and the 1992 Guinness Book of World Records refers to it as the longest real word. This uncountable noun is the act/habit of regarding something as worthless/unimportant. Interestingly, the common English letter E doesn’t occur in this word, while the letter I appears nine times in total. 

Twenty-eight Letters

The sixth longest word in the English dictionary is antidisestablishmentarianism, with 28 letters. It refers to a political philosophy that opposes the withdrawal of state recognition or support from its national Church. This word is considered one the most popular longest words in English in the past decades. 

Twenty-seven Letters

Honorificabilitudinitatibus, the synonym for honorableness, comes seventh on the long English words list, with two other 27-letters-long words being electroencephalographically and antitransubstantiationalist. It means the state of being able to achieve honors. Honorificabilitudinitatibus first appeared as an English word in 1599 and entered Bailey’s Dictionary in 1721 as the longest word in English back then. Additionally, it is the longest English word Shakespeare ever used in his works. 

Electroencephalographically is tied for the seventh longest word in English dictionary, meaning by means of electroencephalography, an apparatus that detects electrical potentials on the scalp and records brain waves. It is the longest unhyphenated word listed in the 10th edition of the Merriam-Webster’s Collegiate Dictionary together with the chemical term ethylenediaminetetraacetate, a salt of Ethylene Diamine Tetraacetic Acid.

Another 27-letter word is antitransubstantiationalist, a religious term that describes someone who disagrees that the consecrated bread and wine can actually change into the body and blood of Christ. 

Translating the Longest Word in English

The longest word in the English language can come in many forms. It could be Taumatawhakatangihangakoauauotamateaturipukakapikimaungahoronukupokaiwhenuakitanatahu, the 85-letters-long place name for a hill near the town of Porangahau in New Zealand. Or it could be Hubert Blaine Wolfeschlegelsteinhausenbergerdorff Sr., the longest personal name ever used that was made up of 747 characters. Whether it’s the medical word pneumonoultramicroscopicsilicovolcanoconiosis or other incredibly long chemical terms, translating such words will require in-country/industry specific linguists who can guarantee the accuracy of its translations based on their linguistic, cultural, and technical knowledge of the subject matter. 

Getting the correct pronunciation of the longest word in English is a Herculean task per se. Not to mention translating it right. That’s why you need to work with professionals. If you need such experts to handle the translation of just about any content from and into English or any other language in the matter, Wordspath is the go-to option! Contact us to further discuss your linguistic needs by hitting the button below.


The longest word in English is not always the same one. As time goes by, new long words will be coined and outrank the old ones on the long words list. In the great world where wonders never cease, which long word lives up to the name of the world’s longest word is really up to your preference. 

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