What is The Longest word in the English Language?
828033
From what I know, poster number 2 is correct.
960990
Due to width limit on Y!A, some of these words are not in their completion and will be noted with an ellipsis (...).  Please visit the sources links for the full spelling.\n\n\n(45 Letters) PNEUMONO­ULTRA­MICRO­SCOPIC­SILICO­VOLCANO­CONIOSIS (also spelled PNEUMONO­ULTRA­MICRO­SCOPIC­SILICO­VOLCANO­KONIOSIS) = a lung disease caused by breathing in particles of siliceous volcanic dust.\nThis is the longest word in any English dictionary. However, it was coined by Everett Smith, the President of The National Puzzlers' League, in 1935 purely for the purpose of inventing a new "longest word". The Oxford English Dictionary described the word as factitious. Nevertheless it also appears in the Webster's, Random House, and Chambers dictionaries.\n\n(37 Letters) HEPATICO­CHOLANGIO­CHOLECYST­ENTERO­STOMIES = a surgical creation of a connection between the gall bladder and a hepatic duct and between the intestine and the gall bladder.\nThis is the longest word in Gould's Medical Dictionary.\n\n(34 Letters) SUPER­CALI­FRAGI­LISTIC­EXPI­ALI­DOCIOUS = song title from the Walt Disney movie Mary Poppins.\nIt is in the Oxford English Dictionary.\n\n"But then one day I learned a word\nThat saved me achin' nose,\nThe biggest word you ever 'eard,\nAnd this is 'ow it goes:\nSupercalifragilisticexpialidocious!"\n\n(30 Letters) HIPPOPOTO­MONSTRO­SESQUIPED­AL­IAN = pertaining to a very long word.\nFrom Mrs. Byrne's Dictionary of Unusual, Obscure and Preposterous Words.\n\n(29 Letters) FLOCCI­NAUCINI­HILIPIL­IFICATION = an estimation of something as worthless.\nThis is the longest word in the first edition of the Oxford English Dictionary. Interestingly the most common letter in English, E, does not appear in this word at all, whilst I occurs a total of nine times. The word dates back to 1741. The 1992 Guinness Book of World Records calls flocci­nauci­nihili­pilification the longest real word in the Oxford English Dictionary, and refers to pneumono­ultra­micro­scopic­silico­volcano­koniosis as the longest made-up one.\n\n(28 Letters) ANTI­DIS­ESTABLISH­MENT­ARIAN­ISM = the belief which opposes removing the tie between church and state.\nProbably the most popular of the "longest words" in recent decades.\n\n(27 Letters) HONORI­FICABILI­TUDINI­TATIBUS = honorableness.\nThe word first appeared in English in 1599, and in 1721 was listed by Bailey's Dictionary as the longest word in English. It was used by Shakespeare in Love's Labor's Lost (Costard; Act V, Scene I):\n\n"O, they have lived long on the alms-basket of words.\nI marvel thy master hath not eaten thee for a word;\nfor thou art not so long by the head as\nhonorificabilitudinitatibus: thou art easier\nswallowed than a flap-dragon."\n\nShakespeare does not use any other words over 17 letters in length.\n\n(27 Letters) ELECTRO­ENCEPHALO­GRAPHICALLY\nThe longest unhyphenated word in Merriam-Webster's Collegiate Dictionary (10th Ed.), joint with ethylene­diamine­tetraacetate (see below).\n\n(27 Letters) ANTI­TRANSUB­STAN­TIA­TION­ALIST = one who doubts that consecrated bread and wine actually change into the body and blood of Christ.\n\n(21 Letters) DIS­PRO­PORTION­ABLE­NESS and (21) IN­COM­PREHEN­SIB­ILITIES\nThese are described by the 1992 Guinness Book of World Records as the longest words in common usage.\n\nSome say SMILES is the longest word because there is a MILE between the first and last letters!\n\nChemical Terms\nTwo chemical terms (3,641 and 1,913 letters long) have appeared in the Guinness Book of World Records. They were withdrawn because they have never been used by chemists, and there is no theoretical limit to the length of possible legitimate chemical terms. A DNA molecule could have a name of over 1,000,000,000 letters if it was written out in full.\n\n(1,185 Letters) ACETYL­SERYL­TYROSYL­SERYL­ISO­LEUCYL­THREONYL­SERYL­PROLYL­S
355483
STRENGHTS...Longest word with one vowel only
22315
"Euouae, six letters long, is the longest English word consisting only of vowels, and, also, the English word with the most consecutive vowels."
1076553
The longest word in any major English language dictionary is Pneumonoultramicroscopicsilicovolcanoconiosis, a 45-letter word supposed to refer to a lung disease, but research has discovered that this word was originally intended as a hoax. It has since been used in a close approxmation of its originally intended context, lending at least some degree of validity to its claim. See the separate article for details.\n\nThe Guinness Book of Records, in its 1992 and subsequent editions, declared the "longest real word" in the English language to be floccinaucinihilipilification at 29 letters. Defined as "the act of estimating (something) as worthless", its usage has been recorded as far back as 1741. In recent times its usage has been recorded in the proceedings of the United States Senate by Senator Robert Byrd [1], and at the White House by Bill Clinton's press secretary Mike McCurry, albeit sarcastically. It is the longest non-technical word in the first edition of the Oxford English Dictionary.\n\nAntidisestablishmentarianism (a 19th century movement in England opposed to the separation of church and state) at 28 letters is one of English's longest words.\n\nThe longest word which appears in William Shakespeare's works is the 27-letter honorificabilitudinitatibus, appearing in Love's Labour's Lost. This is arguably an English word (rather than Latin), but only because he used it.\n\nThe humuhumu-nukunuku-a-pua‘a, or reef triggerfish, is Hawaii's official state fish [1]. At 21 letters (22 counting the okina) it is one of the best known very long one-word names for an animal. It is often asserted that "the name is longer than the fish."\n\nAlthough only fourteen letters long, sesquipedalian deserves a mention. It is derived from a nonce word used by the Roman author Horace, in his work Ars Poetica (The Art of Poetry). The quote is as follows: "Proicit ampullas et sesquipedalia verba," which means, "He throws aside his paint pots and his words that are a foot and a half long". The Oxford English dictionary[2] lists sesquipedalianism ("the practice of using words one and a half feet long"), and further derivations can be created as described in the Constructions section below.
135850
if you mean the longest word, i believe the longest word in the dictionary is antidisestablishmentarianism
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OMG OMG I ABSOLUTELY LOVE WORDS!!!!!!! I AM THE WORD FREAK OF MY SCHOOL I CARRY A DICTIONARY AND THESAURUS TO EVERY CLASS AND MY NICKNAMES ARE MISS WEBSTER 2006 AND DICTIONARY GIRL!!! I LOVE IT WHEN PEOPLE ASK ME THIS QUESTION!! It's hard to choose though!! I love them all so much! Okay, one of my favorites would have to be idiosyncratic, which means weird in one's own way, or strangely unique! My newest favorite is pneumonoultramicroscopicsilico-\nvolcanoconiosis, which is a supposed disease contracted from the overinhalation of silica dust. The disease does not really exsist, but that word is still my favorite, because it is the longest one I know! And, I can flawlessly spell it without looking! I have yet to find the longest word ever, though, but I can do it!
581440
The CORRECT spelling for the longest word currently in the English language is:\n\nPneumonoultramiscroscopic\nsilicovolcanoconiosis\n\n46 letters long.  It is an inflammatory lung disease caused by the inhalation of fine silica dust.
757566
The longest word currently listed in Oxford dictionaries is rather of this kind: it is the supposed lung-disease pneumonoultramicroscopicsilicovolcanoconiosis (45 letters)\n\nSome editions of the Guinness Book of Records mention praetertranssubstantiationalistically (37 letters), used in Mark McShane's Untimely Ripped (1963), and aequeosalinocalcalinoceraceoaluminosocupreovitriolic (52 letters), attributed to Dr Edward Strother (1675-1737).
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PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS (45 letters; a lung disease caused by breathing in certain particles) is the longest word in any English-language dictionary.
665766
Twyndyllyngs is the longest word without any of the common vowel letters a, e, i, o, or u (although y is certainly a vowel in that and many other words). Euouae, at six letters long, is the longest English word consisting only of vowels.
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antidisestablishmentarianism:  The longest word in the dictionary.
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PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS (45 letters; a lung disease caused by breathing in certain particles) is the longest word in any English-language dictionary. (It is also spelled -koniosis.)
371996
FLOCCINAUCINIHILIPILIFICATION (29 letters; an estimation of something as worthless) but technically, this is no longer the longest word in the dictionary. This one is: PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS (45 letters; a lung disease caused by breathing in certain particles) is the longest word in any English-language dictionary. (It is also spelled -koniosis.)
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No such word in the English language. What language is it from?
1045114
The longest word that I could find having only 4 letters is serenenesses - 12 letters long using only S,E,R,N
833113
The longest non-technical word is flocci­nauci­nihili­pili­fication at 29 letters. Consisting of a series of Latin words meaning "nothing" and defined as "the act of estimating something as worthless," its usage has been recorded as far back as 1741.In recent times its usage has been recorded in the proceedings of the United States Senate by Senator Robert Byrd, and at the White House by Bill Clinton's press secretary Mike McCurry, albeit sarcastically