In an orthographic episode of the PBS series Otherwords, host Dr. Erica Brozovsky, Ph.D. of the University of Texas at Austin analyzed those words that are considered to be the longest in the world. In order to do this, Brozovsky determined that the word “word” must be defined, as those words previously thought to be the world’s longest in the English language were really formulas, regulations, compound words, or even the name of a town in Wales.
If we’re going to find a more satisfying answer to this question, we’ll have to dig deeper into what the word, word really means.
Rather than looking for the words with the most letters, Brozovsky looked to the longest words that are used in the commonly shared lexicon of modern times. From there she pinpointed three words “internationalization”, “incomprehensibilities”, and “uncharacteristically”.
These are three of the longest, non-spaced, non-hyphenated English words that are considered “in common usage”. If these slip past your ear without slowing down your comprehension, then we could safely call these part of your shared vocabulary and strong contenders for the longest, commonly used word in English, to you.