Sesquipedalian

[Becky]

Measuring or containing a foot and a half; as, a
sesquipedalian pygmy; -- sometimes humorously applied to long words.

[Tanya Shivari]

An extraordinarily [large] word. [A word] that only the [pedantic] use.

[Dianne]

[ses]·qui·pe·da·[lian]
n.
A long word.
adj.

Given to the use of long words.
Long and [ponderous]; polysyllabic.

[Couch Potatoe]

A lover of words; particularly [long words]. These people dont merely love these words, they lust these words, they fantasize about them, they fucking ADORE THEM!

The lives of Sesquipedalians are words, they live, breathe and eat words. Literally. Extreme Sesquipedalianism (or ES) is a condition whereby a patient reports excessive masturbation and [intrusive] sexual thoughts about words. Treatment is [sparse].

[Kit]

Let’s start off with a word related to the business of “longest words.” Sesquipedalianism is the tendency to use long words. And, a sesquipedal is a person who has [sesquipedalian] tendencies.

The word is traced to the ancient Roman poet Horace, who in a [treatise] on crafting poetry, wrote that in certain circumstances, one must avoid [sesquipedalia verba], a Latin construct meaning “words a foot and a half long.” Horace clearly had a sense of humor. (Source- Dictionary.com)

[Raeanne Dimick]

A [big ass] [word that] can be used to describe someone that uses big ass [words]

[Sommer]

[adj]. Characterized by [long words]; long-winded

[Renato]

(of a word) polysyllabic; long.