Reading at the Speed of Thought TM 0 items Sign In Register Home Online Courses Live Classes Apps Blog About Us Contact https://irisreading.com/10-longest-words-in-theenglish-language/ 10 Longest Words in the English Language Last Updated: Dec 30, 2019 How many words exactly are in the English language? The second edition of the current 20volume Oxford English Dictionary contains 171,476 words in current use. That’s a lot! Which gets the mind thinking the next question, what’s the longest word in current use today? Many of the longest words in the dictionary refer to medicine or chemistry. You’ll find a few defined in here along with other long words that you may or may not already use. Here’s how Merriam-Webster defines the ten longest words in the English language. 1. Pneumonoultramicroscopicsilicovolcanoconiosis (45 letters) Pneumoconiosis caused by inhalation of very fine silicate or quartz dust. 2. Hippopotomonstrosesquippedaliophobia (36 letters) Ironically, Hippopotomonstrosesquippedaliophobia is one of the longest work in the dictionary and is the name for a fear of long words! Who would have thought, right? 3. Supercalifragilisticexpialidocious (34 letters) Perhaps the best word of all! Made popular by the film Mary Poppins, Supercalifragilisticexpialidocious is something to say when you have nothing to say. 4. Pseudopseudohypoparathyroidism (30 letters) A relatively mild form of pseudohypoparathyroidism that is characterized by normal levels of calcium and phosphorus in the blood. 5. Floccinaucinihilipilification (29 letters) The longest unchallenged nontechnical word that not all directories recognize, that including Merriam-Webster. According to alternative sources, floccinaucinihilipilification is the act or habit of describing or regarding something as unimportant, of having no value or being worthless. Often times, it is used in a humorous way. Free Speed Reading Class – Click Here To Register 6. Antidisestablishmentarianism (28 letters) A term referring to a political movement in 19th century Britain that sought to separate church and state. In this case, political movement wanted to disestablish the Church of England as the official state church of England, Ireland and Wales. 7. Honorificabilitudinitatibus (27 letters) The longest word in Shakespeare’s works. Honorificabilitudinitatibus is the longest word in the English language featuring alternating consonants and vowels. 8. Thyroparathyroidectomized (25 letters) A medical term that defines the excision of both the thyroid and parathyroid glands. 9. Dichlorodifluoromethane (23 letters) A chlorofluoromethane CF2Cl2. 10. Incomprehensibilities (21 letters) Impossible to comprehend. In the 1990’s, incomprehensibilities set the record as the longest word “in common usage.” LONGEST ENGLISH WORD:Methionylthreonylthreonylglutaminylarginyl…isoleucine (189,819 letters) If we’re talking chemistry, the longest chemical name is 189,819 letters long. It is the chemical name for titin, a giant filamentous protein essential to the structure, development, and elasticity of muscle. As to whether or not this is an actual word is disputed by many. It is not in the Merriam-Webster dictionary, so you shouldn’t ever have to worry about spelling it. ? What is Dyslexia and the Systematic Approach to Treatment What is Spaced Repetition and How Does it Improve Your Memory? 182 June 28, 2019 by Danielle in Article Comments Susan R Stephenson March 10, 2021Reply Thank you all. That was fun and I like knowing there are so many of us logophiles “word nerds” or sesquipedalianophiles (someone one who loves long words – I think I made this up – sort of) out there :) AlwaysThinkPositive March 2, 2021Reply Anti-counterrevolutionaries Some Other Words February 8, 2021Reply radioimmunoelectrophoresis (26), u need defenition so it means: radiommunoelectrophoresis in which the substances separated in the electrophoretic system are identified by radioactive labels on antigens or antibodies. psychoneuroendocrinological (27) means: it is the clinical study of hormone fluctuations and their relationship to human behavior. It may be viewed from the perspective of psychiatry, where in certain mood disorders, there are associated neuroendocrine or hormonal changes affecting the brain. quinquagintaquadringentilliard (30) it’s some really high number o Evan February 18, 2021 Skewes number might be an even larger number because it is equal to 10 to the 10th power to the10th power to the 34th power. hi February 4, 2021Reply you forgot greatgreatgreatgreatgreatgreatgrandfather lol Karishannaliyamiyesariasheleya February 4, 2021Reply ‘Karishannaliyamiyesariasheleya’is my name 😊 Anonymous January 27, 2021Reply That’s nice 😊 Jagged Peak December 3, 2020Reply Methanidylidynesilanylium has 25 letters and is the chemical compound of silicon and carbon, a.k.a. silicon carbide! o zawwar Mehboob December 11, 2020 Perhydrocyclopentanophenanthrene its even longer its a cholesterol compound. olivia December 2, 2020Reply why would anyone make a 189,891 letters long word Alek Sander November 3, 2020Reply The longest words belong to Science! nonanonacontanonactanonalia November 3, 2020Reply nonanonacontanonactanonaliagon is longest name for a polygon o hehe December 3, 2020 Rhombicosidodecahedron is one of my favorites o Alek Sander December 15, 2020 Nonanonacontanonactanonaliagon is a 9,999-sided polygon. Cole the 10 year old October 30, 2020Reply what about precipitevolissimevolmente which is a 26-letter-long adverb. sksk October 30, 2020Reply ummmm another word with 27 letters is ethylenediaminetetraacetate that you forgot Christopher Nowak BFA MLIS October 28, 2020Reply Deinstitutionalisation and Counterrevolutionaries??!! o rhonda November 6, 2020 what about rhombicosidodecahedron Kyliah Williams October 19, 2020Reply This Website Is Pretty Cool! 😎 o Zie February 3, 2021 These words are making me Supercalifragilisticexpialidocious🤣🤣🤣🙌 yup meeeeeeeeeeee Pneumonoultramicroscopicsilicovolcanoconiosis October 12, 2020Reply tetrahydrocannabinol (20 letters): tetrahydrocannabinol stands for psychoactive substance present in marijuana. yup meeeeeeeeeeee Pneumonoultramicroscopicsilicovolcanoconiosis October 11, 2020Reply forget hyperbetalipoproteinemia (24 letters): hyperbetalipoproteinemia stands for a genetic disorder characterized by high levels of beta-lipoproteins and cholesterol. THE LEGEND October 5, 2020Reply Longest place name = llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch o yup meeeeeeeeeeee Pneumonoultramicroscopicsilicovolcanoconiosis October 13, 2020 Nope, Taumatawhakatangihangakoauauotamateaturipukakapikimaungahoronukupokaiwhenuakitanatahu, New Zealand The world’s longest place name belongs to a hill near Porangahau in the southern Hawke’s Bay in New Zealand. It is a name given in the Maori language. This hill is 305 meters tall and is famously known for its long name. This name has since been shortened to Taumata for the ease of pronunciation. The meaning of the name has been translated to mean “the place where Tamatea, the man who had big knees, the climber of mountains, the slider, the land-swallower that traveled about, played the nose flute that he had to the loved ones.” With 85 characters, it is the longest place name in the world according to the Guinness World Records. Lily September 7, 2020Reply I just LOVE this website. o Alek Sander September 9, 2020 This website loves you too! o Matt October 18, 2020 Paramethoxymethaphetamine has 25 letters. Forgot about it. o …. November 3, 2020 wow im late on the website Alek Sander November 3, 2020 Never be late again! Speed Reading & Memory Bootcamp Series. Bryan Phillips August 31, 2020Reply Methylphenidate or in shampoo methylisothiazolinone and methylisothiazide tributyline is a fat compound methyltertiarybutylether methylbutyltertiaryether and ethyltertiarybutylether in gasoline were damaging engines especially small engines and are no longer used. I used to be a mechanic o Jaz December 9, 2020 And Methylchloroisothiazolinone, mah dude 😎 Hippopotamus August 28, 2020Reply What about kakorrhaphiophobia? Fear of failure o Turtle October 13, 2020 Isn’t that just being normal Emmanuel August 17, 2020Reply The word “Tmesis” is more incredible than long words. Vinoth August 17, 2020Reply Tamil language has 247 letters o Gabriella October 18, 2020 Wow I can’t believe this Bradley Ross August 11, 2020Reply Antidisestablishmentarianism actually has the definition for disestablishmentarianism. The attached sound clip has the definition correct. What is also interesting is that antidisestablishmentarianism is recognized by my spell checker but disestablishmentarianism is not. o George August 13, 2020 Agreed – anti-definition. What about AntidisestablishmentarianismIST! someone August 10, 2020Reply transdifferentiation o Gerry jones August 28, 2020 I love long words. I wish all words were longer. idefkwtf July 31, 2020Reply Just imagine you having to be a doctor and telling the patients you have Methionylthreonylthreonylglutaminylarginyl…isoleucine for 3 hours and they are already dead and you keep going on and on, even at the freaking funeral! o lololol August 10, 2020 Teacher: ok kids, how do you spell Methionylthreonylthreonylglutaminylarginyl…isoleucine? Kids: O_O 🐲🦄😇😸 July 28, 2020Reply Hippopotomonstrosesquippedaliophobia means fear of long words and is a long word!! Robo July 28, 2020Reply Amazing!! ^_^ July 8, 2020Reply Please add this word and put it on the 12th place (19 letters) Chlorofluorocarbons and put this on the 11th place (24 letters) hydrochlorofluorocarbons o ^_^ July 8, 2020 I meant put hydrochlorofluorocarbons on the 9th place o Hippopotamus August 28, 2020 Electroencephalographically o -_October 31, 2020 thought chlorofluorocarbons isn’t counted as a long word James Mangong Ngor Ajang July 7, 2020Reply I have never ever come accross such English words.It’s a great surprise. scottish.cow June 22, 2020Reply what about polyetherketoneetherketoneketone Leah June 21, 2020Reply Some people have Hippopotomonstrosesquipedaliophobia and then there’s me who has Hippopotomonstrosesquipedaliophilia!! Zainab June 12, 2020Reply I am only 9 years old and I know the words pneumonoultramicroscopicsilicovolcanoconiosis o Abi July 21, 2020 Cool Unknown June 3, 2020Reply this is Supercalifragilisticexpialidocious Oh yeah yeah June 2, 2020Reply I learned a new word to flex with :] Pneumonoultramicroscopicsilicovolcanoconiosis Rather not say May 31, 2020Reply I knew the first three and can pronounce the first but really no. 2, ironic how are the sufferers meant to say their condition o kay June 11, 2020 facts No May 29, 2020Reply 29 letters Methylenedioxymethamphetamine, Tsehesenestsestotse May 26, 2020Reply You missed spectophotofluorometrically, but I don’t know the definition o Alek Sander May 27, 2020 A spectrophotofluorometre is a tool for assessing the amount of light given off by something, so in its 28-letter adverbial form, we could use a sentence like “the sample was assessed spectrophotofluorometrically.” BrUh May 24, 2020Reply The fear of long words’ name is ironic o Alek Sander June 5, 2020 Aaaaaaaaaaaaaaaaaaaaaaahhhhhh!!!!!! o Hippopotamus August 5, 2020 What about electroencephalographically Alek Sander August 8, 2020 Sure – Electroencephalograph in it’s adverbial form would be electroencephalographically (27 letters). Lemony Snicket lover56 May 23, 2020Reply Some of these words are confusing to spell I can’t even remember them all!!! I like pronouncing them though. o Lemon Zest ( O-O ) August 26, 2020 Me too! They are fun to pronounce not going to say my name May 14, 2020Reply you missed out a word which is 24 letters long: Lymphangioleiomyomatosis (it’s a disease of the lungs) Unknown May 13, 2020Reply What about antimonopologeographicationalism yeet May 12, 2020Reply I watched the whole video of the longest word, a great waste of a hour. o Alek Sander June 5, 2020 I watched it twice just to make sure. You’re right. Iorwuese Lubem Amos May 12, 2020Reply I never even knew that this kind of words exist self i try to check on Google today to see and to my greatest amazement i found it na so things they this world unless you research and see by yourself…. Mikaela May 12, 2020Reply Super long words! o Adriana June 16, 2020 Yep! o Johm M Sims July 22, 2020 Somewhere in the middle belongs a word I learned today in nursing school …..Esophagogastroduodenoscopy….26 letters Shahryar May 5, 2020Reply I offer this 20 word for number 11: Compartmentalization Jayden April 28, 2020Reply I forgot what it’s called but the fear of the number 666 is a long word o Alek Sander April 28, 2020 Hexakosioihexekontahexaphobia o Jessica Khumalo June 5, 2020 I was astonished to by the compartmentisation , but guess the ones introverted are homogeneous to science but slightly heterogeneous .. Fireproofsquirrel April 22, 2020Reply What about antidisestablishmentarianism? o Alek Sander April 23, 2020 Yup, it’s listed at #6 in the post. # yourcommentreader.. April 19, 2020Reply This website comments just made my day 😆 o Jennifer April 20, 2020 lol o Kay May 20, 2020 Lol along with Jennifer Bee April 16, 2020Reply Common usage? – ‘compartmentalisation’, 20 letters- read in a few papers today and thought ‘that’s a long word’ and so here I am. o Trisha April 24, 2020 I was bored and I googled a word and here I am. Someone posted the longest girls name is next. Lmao Chris April 11, 2020Reply Yesterday dust entered my lungs and this site helped me coz now I know that the disease I have is pneumonoultramicroscopicsilicovolcanoconiosis o COWS ARE COOL May 13, 2020 how about friggatriskaidekaphobia? It’s the fear of Friday the 13th. Unicorn 🦄 April 8, 2020Reply I love the longest one! 😂 Divyesh April 4, 2020Reply What is the longest word ever?! o Alek Sander April 5, 2020 You won’t find it in the dictionary, but this English word has 189,819 letters (Methionylthreonylthreonylglutaminylarginyl…isoleucine). There’s a video posted above just in case you want to know how to pronounce it. o Umesh Kumar Chaudhary April 6, 2020 Great LifeLang 09 April 2, 2020Reply The last word has lots of “Y”s. Jane Gwyneth Caballa April 1, 2020Reply notice they didnt put DDTDichlorodiphenyltrichloroethane(31) steven April 1, 2020Reply who created the last word from the list it was too long for me so when I watched it I didn’t even watch 1minute then I just closed my MacBook Pro.😂 o James June 11, 2020 Lol steven April 1, 2020Reply Some videos say subscribe even if it’s just telling long words a few times.😂 Steven April 1, 2020Reply wow so long words I think that I am having a fear of long words😀 o Alek Sander April 5, 2020 😂 Beata Wasil March 26, 2020Reply Doctor: You have got the fear of long words. Man: What is the proper name for that? Doctor: Its called Hippopotomonstrosesquippedaliophobia. Man: *Screams and runs away* o Alek Sander April 5, 2020 😂 o Calskee August 11, 2020 Hilarious! Super Cat March 25, 2020Reply Thanks iris for helping me with my assignment today. Thanks to you I feel Supercalifragilisticexpialidocious!!!!!!!🙏🏻😁😻� ❤️❤️ Super Cat March 25, 2020Reply At my school I have 3 Mary Poppins fans. All the time they say Supercalifragilisticexpialidocious and I never knew what that meant, but now I know thanks to this app. And I think its a funny 😄 word to say. 😁😁 Scriptingtalez script March 25, 2020Reply I memorize 3 the Supercalifragilisticexpialidocious, Hippopotomstrosesquippedaliaphobia, and Pneumonoultramicroscopicsilicovolcanoconiois o Pneumonoultramicroscopicsilicovolcanoconiosis April 22, 2020 still didnt spell the last one right. Meee March 23, 2020Reply Rhombicosidodecahedron is a poloygon and it is 22 letters Muhesi Joab March 20, 2020Reply So many but not easy to pronounce Sheryl Limon March 15, 2020Reply ❤ Lukas March 9, 2020Reply for all you people who like words that nobody knows, zyzzyva (a type of tropical weevil) is the last alphabetical word. o Lukas March 9, 2020 also i advise that you guys add hepaticocholangiogastrostomy. o Lukas March 9, 2020 it has 28 it ties for 6th place PewDiePie March 8, 2020Reply Soooooooo long words! I think I am going to get hippopotomonstrosesquippedaliophobia!!! o Alek Sander March 9, 2020 Lol… Best comment so far! Falguni Sharma March 4, 2020Reply This was mind boggling stuff I’ve come across in a long time. Keep on penning down such blogs often. o Laura Grugle March 16, 2020 The biggest word than I’ve ever known was Pneumonoultramicroscopicsilicovolcanoconiosis 100123 March 4, 2020Reply Coooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo ooooooooooooooooooooooool. Tshepo Rasello March 3, 2020Reply those are some long words but it only took me a few minutes to learn pneumonoultramicroscopicsilicovolcanoconiosis JJM March 1, 2020Reply Whatever happened to “semiphotospectroheliographically” Lina Fei February 26, 2020Reply How about Tetaumatawhakatangihangakoauaotamateaurehaearuripukapihimaungahoronukup okaiwhenuaakitanarahu o Alek Sander March 2, 2020 I can’t find any information that this is a real word. Source please. o hi May 13, 2020 it is the name of a hill in New Zealand. soo· pr· ka· luh· fra· juh· li· stuhk· ek· spee· a· luh· dow· shuhs February 21, 2020Reply How did Supercalifragilisticexpialidocious become a real word in the dictionary from a show? And yes I am too lazy to search it my self. Also, the girl with the longest name try and beat that. o Ofre Timothy otiede March 12, 2020 Which one is the shortest in the dictionary o Hippopotamus August 5, 2020 The shortest word without vowels is Cwtch, but the shortest word with vowels is euouae. But basically, A and I are the shortest words ever o stephanie October 26, 2020 what does supercalifragilisticexpialidocious mean Alek Sander October 26, 2020 Use your imagination. Walt Disney encouraged imagination. o Cole the 10 year old October 30, 2020 MARY POPPINS MAN!! BillGates February 20, 2020Reply good job Gail Warren February 20, 2020Reply paradimethylaminobenzaldehyde o Alek Sander February 24, 2020 Oooooh good one! o Hippopotamus August 27, 2020 Establishmentarianism, establishmentarian, antiestablishmentarianism (don’t know if it’s fully considered a word). o Arjun December 9, 2020 Micropachycephalosaurus has 23 letters, too! shelley January 21, 2020Reply wow, looooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong English word! Joshua Griffiths January 15, 2020Reply wow good job for pronouncing that long word your amazing!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1 Sam January 3, 2020Reply what about supercalifragilisticexpialidocious? o Mujtaba April 21, 2020 It means fantastic o Emerald March 8, 2021 The best word around Backnineblues December 27, 2019Reply How about “uncharacteristically” o Abimbola September 27, 2020 Yup we’re living in a floccinaucinihilipilification world however it’s supercalifragilisticexpialidocious when life is faithful to us Harry Green December 27, 2019Reply Common long word: Uncharacteristically – 20 digits o David February 19, 2020 Amorphophalouscompanulatuse Alek Sander February 24, 2020 This is great. The comments are making this the best blog post ever!!! o Kevin February 20, 2020 credit for you people commenting and a person who made this o Ella February 24, 2020 digits are for numbers, letters are for words XxSmartiexX December 20, 2019Reply floccinaucinihilipilification-the estimation of something as worthless – 29 letters. o XxSmartiexX December 20, 2019 sry didnt see it up there IM NOT A ROBOT (OR AM I) December 16, 2019Reply Euouae is the longest word with only vowels. o XxSmartiexX December 20, 2019 what does it mean? o This Is You January 3, 2020 yeah what it mean o Don’t be Lazzzy peeps January 15, 2020 look it up, y’all have internet o Hippopotamus August 28, 2020 Euouae (/ju:’u:I:/) or Evovae is an abbreviation used in Latin psalters and other liturgical books to show the distribution of syllables in the differentia or variable melodic endings of the standard Psalm tones of Gregorian chant. Me (AGAIN) December 16, 2019Reply Methionylthreonylthreonylglutaminylarginyl…isoleucine, longest known protien. It has 189,819 letters. Idk November 27, 2019Reply Hexakosioihexekontahexaphobia 29 characters is the fear of the number 666 o Anonymous December 29, 2019 =Plz add da protein that has 189819 letters. PLS Alek Sander December 30, 2019 Done! Bobby Bentrus November 25, 2019Reply chlorofluoromethane almost made it! That was funny Paul Nowak November 23, 2019Reply This post was just updated to include videos with pronunciation. Good luck trying to verbalize these words! Unknown November 22, 2019Reply What about PSEUDOPSEUDOHYPOPARATHYROIDISM?? o Unknown November 22, 2019 Its 30 letters so it would fall as 4th or 5th place in this. o Paul Nowak November 23, 2019 Good catch. Updated! o Me (AGAIN) December 16, 2019 Methionylthreonylthreonylglutaminylarginyl…isoleucine, longest known protien. It has 189,819 letters. TOO LONG Nancy November 22, 2019Reply I am reading this because of my school compdition ? Jaxson November 18, 2019Reply Wheres Hippopotomonstrosesquipwdaliophobia. It’s 35 letters. georgie November 13, 2019Reply dichlorodiphenyltrichloroethane is 31 letters. It’s a chlorine compound o Alek Sander November 18, 2019 That’s a good one. Thanks! We’ll update the post. basher November 12, 2019Reply what About Congratulations ? Harshee Patel November 11, 2019Reply These are words I’ve never heard o xXYeahItsMeCreeperXx November 18, 2019 what the @:!? they made that words but,How about Marshmallow? Alek Sander November 18, 2019 Marshmallows are delicious! o technocrat March 12, 2020 Several of them were really just made up for the purpose of creating ridiculously long words. For example, pneumonoultramicroscopicsilicovolcanoconiosis is not a legit medical word. You won’t find it in any medical dictionary. The words for what it means are pneumoconiosis (pneumonitis caused by fine particles/dust) and silicosis (pneumonitis caused by silicon particles). I’ve seen those 2 combined into pneumosilicosis and *maybe* even pneumosilicoconiosis, but DEFINITELY not the 45 letter version. bob November 8, 2019Reply that is a good word ??? October 29, 2019Reply This is a good website but you could also add Antidisestablishmentarianism which has twenty-eight letters and is originally described opposition to the disestablishment of the Church of England, but now it may refer to any opposition to withdrawing government support of a particular church or religion. o Paul Nowak November 5, 2019 We have updated our post to reflect your added wisdom! Thank you! o @feminoofdips March 9, 2020 Mrs gargantuan I caught you here ?? KAREN BLUMENTHAL October 16, 2019Reply YOU LEFT OUT HIPPOPOTOMONSTROSESQUIPPEDALIOPHOBIA FEAR OF LONG WORDS…. o Oh my goodness November 7, 2019 That’s literally what I came here for… also it’s hippopotomonstrosesquippedaliophobia… that’s too long to write here (0^0) o Hannah November 9, 2019 Is that actually a thing o bro November 13, 2019 Yes don’t forget hippopotomostreusquippdeloilaphobia Alek Sander November 18, 2019 Thanks! We’ll update the post. o Paul Nowak November 23, 2019 Updated. #2 on the list! o technocrat March 12, 2020 hippopotomostreusquippdeloilaphobia, like some of the other words on this list, were really just made up for the purpose of creating really long words. The more widely accepted word meaning ‘fear of long words’ is sesquipedalophobia…still long enough to be ironic and funny ;) o Cole the 10 year old October 30, 2020 No that was the second one on the list. Or third. Or fourth. I HAVE NO IDEA Save my name, email, and website in this browser for the next time I comment. Add Comment Free Speed Reading Course $0.00 FREE Mini Class Video-based Training Register Free Speed Reading Classes *Get On The Waiting List Class Updates Enter Your Email Address City & State (or Region) Check Availability If you are human, leave this field blank. Austin Boston Chicago Columbus Dallas DenverHong KongHouston Las Vegas LondonLos Angeles Miami Minneapolis Montreal New York Orange County Philadelphia Portland San Diego San Francisco SeattleSingaporeToronto Vancouver Washington DC Other Cities Sign Up for an Online Course Copyright © 2022 Iris Reading, LLC All trademarks & Logos are the property of their respective owners. Terms of Use Privacy Affiliates Contact Us Xcvbnm,asdfghjklaaaaAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAAAAAAAAAAAAAAAAAAAA