Sesquipedalian (adj.)
(Of a word) Containing many syllables.
(Of a person) Having an advanced vocabulary.
Loquaciousness (adj.)
(Of a person) Having a tendency to talk a lot; garrulous.
(Of a sentence) Using far more
words than necessary; verbose.
Therefore, "Sesquipedalian Loquaciousness" refers to the tendency of a (usually) highly intelligent person to
use extremely large
words in mass quantities in order to sound more intelligent. Commonly found in
chemistry and other ambitious majors.
Done right, it makes the person sound
like someone who oughta be respected and paid attention to, because they definitely know what they're talking about.
Done wrong, it makes the person sound condescending and/or pretentious.