Longest English Word, according the The Bulletin 1918
The question of what is the longest word in the English language came up in connection with certain scientific, chemical words which cannot strictly be entered as claimants for the distinction. They are really compound words and are generally printed with a hyphen though they are sometimes used as one word. If they were admissible they would easily be winners. Ethyldioxydihydroteraphthalate, for example, is one, for which see Catalogue of Public Documents of the Sixty-Third Congress, p. 1832. This, however, is surpassed by methylethylpropylisobutylammoniumchloride which may be found in "Organic Chemistry for advanced Students" by Julius B. Cohen, New York, 1919, p. 620.
'Probably the longest regular, dictionary word in English is or was honorificabilitudinity. The definition given is honorableness. It is fortunately obsolete and was rare at that See the Murray-Oxford Dictionary where there is appended the following example of its use: "1800 Spirit Pub. Jrnls. (1801) IV. 147. The two longest monosyllables in our language are strength and straight, and the very longest word is honorificabilitudinity."
From the Dictionary of Phrase and Fable By Ebenezer Cobham Brewer
Agathokakological. (Southey: The Doctor.)
The giantess. (Croquemitaine, iii. 2.)
(The Three Hairs.)
One of the books in the library of St. Victor. (Rabelais: Pantagruel, ii. 7.)
(battle of the frogs and mice). A Greek mock heroic.
called the longest word in the (?) English language. It frequently occurs in old plays. (See Bailey's Dictionary) . The "quadradimensionality" is almost as long.
"Thou art not so long hy the head as Honorificatbilitudinitatibus." Shakespeare: Love's Labour Lost, v.1.
Inanthropomorphisability of deity.
They morramborizeverzengirizequoquemorgasaebaquevezinemaffretiding my poor. eye. (Rabelais: Pantagruel, iv. 15.)
A dye of an intense red colour.
"Dinitroaniline, cbloroxynaphthalic acid, which may be used for colouring wool in intense red; and nitrophenylenediamine of chromatic brilliancy."- William Crookes: The Times, October 5th, 1868.
"Why. not wind up the famous ministerial declaration with 'Konx Ompax' or the mystic 'Om' or that difficult expression Polyphrasticontinomimegalondulaton'"-The Star
"The general depth of modern researches in structural chemistry must he explained, even to those, who are not interested in the mystery of tryphenylmethans, the tetramethyldiamidobenzhydrols and other similarly terrific terms used by chemists."-.Nineteenth Century (Aug., 1893, p. 248).
From The King's English By George Washington Moon:
Words derived from the Saxon are usually very short in comparison with those of Latin origin, but some words of even Saxon derivation are polysyllabic, e.g. "straightforwardness," "forethoughtfulness," "unthoroughfaresomeness," meaning (in a word of Latin derivation), "impenetrability." Three of the longest words in the English language are "latitudinarianism," "attitudinarianism" and "platitudinarianism;" each has nine syllables. These three words, which are not only the longest words, but the longest rhyming words, in the English language, have satirically been said to be descriptive of the three divisions of the English church. The following is a German word,—
meaning, A Constantinopolitan itinerant bagpipe player.