Sesquipedalian: A protracted element of one's lexicon, or characterized by the apparent use of such. From a Latin etymology loosely translating as "a foot and a half long."
Loquaciousness: That would be garrulousness, verboseness, effusiveness. How about "chattiness"?
A predilection by the intelligentsia to engage in the manifestation of prolix exposition through a buzzword disposition form of communication notwithstanding the availability of more comprehensible, punctiliously applicable, diminutive alternatives. Occasionally referred to, in layman's terms, as "gross verbosity". Related to this trope is the concept colloquially known as "inkhorn terms", neologisms that originate from a foreign language, such as Medieval Latin or Old French, rather than Anglo-Saxon words, which are supposedly more untroublesome for American English speakers to comprehend.
To be frank, "geniuses" in television shows prefer to use a lengthy vocabulary when it would be easier for most of their peers to comprehend a much simpler lexicon, especially when the aforementioned characters are known for speaking rather quickly. Characters afflicted with this apparent trait oft are known for being overly complicated in speaking, as writers appear to believe that this manner of speech is the only obvious manner to display that one is more perspicacious than the supposedly average script-writer. This could also be the trait of a particularly obnoxious character who feels that he always has to be correct on his assumptions, this behavior extending far enough that this character always feels like he has to use only what he feels is exactly the "correct" word — never using "blue" when "azure" or "indigo" or even "royal blue" would be more accurate, for example.
Occasionally, such characters might potentially cease the use of this manner of speech if things get particularly climacteric, to emphasize exactly how dreadful the direction the current events are heading towards is (in the same manner as Sarcasm Failure). Alternatively, they might potentially become even more verbose as they get more hysterical, leading to increasingly detailed but ultimately incoherent ranting that seems similar to wangst. Frequently, a different character might potentially remark with a sentence like "Wouldn't it be easier to just [whatever the brainy person said, in layman's terms]?" or, alternatively, "And [layman's terms version], too!"
Ironically, Williams Syndrome can potentially lead to this manner of behavior. Those who suffer from Asperger's Syndrome might behave in this manner in an apparent attempt to act as precise as possible, ironically making their oratorical sonorities too pleonastic to be expeditiously assimilated.
One of the frequent symptoms of Spock Speak. Is typically a Motor Mouth. Is fitting is one has an accent originating from the United Kingdom of Great Britain and Northern Ireland. Often known for taking an advantage of the fact that that Talking Is a Free Action. Related trope articles are the following: Techno Babble, Expospeak Gag, Antiquated Linguistics, Sophisticated as Hell, and Department of Redundancy Department. If one attempts this and can not seem to use the right lexicon, they're perpetrating Delusions of Eloquence. If the author is guilty of this, it is Purple Prose. The word Antidisestablishmentarianism is typically common, as well.
Popularized and associated with Steampunk and its related genres, and it is a correct assumption that the Victorians would speak in such a manner, as the English of the time was far more complicated than that of today.
It may also be worth noting that there is, in fact, a word for the irrational fear of long words; ironically, the word is "sesquipedalophobia", which is oft exaggerated by some as "hippopotomonstrosesquipedaliophobia".
The exact antilogy of Buffy Speak and Layman's Terms. "Big Words" redirects here, for those who might not understand certain long words. Contrast with the Laconic Wiki. Also of note is the apparent similarity, and possible relation, to Techno Babble. May require one to possess a Translator Buddy.
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