Why “sesquipedalianist” is a great word
A person who habitually uses and delights in long and polysyllabic words. From sesquipedalian (from Latin sesquipedalis, "a foot and a half long") + -ist (agent suffix). Unlike a logophile, whose affection is for language in all its forms, or a pedant, whose primary concern is a showy adherence to rule, a sesquipedalianist finds a peculiar beauty in sheer lexical magnitude. It is the deliberate, rolling cadence of an obscure adjective, the pleasant weight of a twelve-syllable term in plain speech, or the defiant flourish of a polysyllabic word where a short one would do—the dinner guest who deploys "eleemosynary" when "charitable" would suffice, the quiet celebration of the ornate in a world that prizes the plain, where meaning is more satisfying when it arrives breathless and overburdened.
Definitions & examples from Wiktionary (CC BY-SA 3.0).