When someone uses a needlessly complicated or esoteric word when a simpler word or expression would suffice.
A common occurence amongst neophyte academics who wish to impress peers.
Why did you say "lacuna" to just say that he had a "break" or "opening" in his schedule? That was a needless vocabularical bitch slap.
At a greater intelligence of vocabulary. To be vocabullarically inclined you must have a greater knowledge of vocab then peers and the people around you.
Johnny is vocabullarically inclined. He outsmarts everyone in English class.