Someone who repeatedly uses large, complicated words when only the basic word is required and/or jumbles up words together that don't have the same meaning as intended. (Attempting to sound smarter than they actually are.)
Prof: Now who can explain the theory?
Student: I obtain the ability!
Prof: Okay Michelle, go ahead.
Student: I have high doubts in the cognitive processes of this theorist as he continually demostrates excavating premonitions about the ongoing insanities of the homo sapien population. His theory contradicts all predescendant foreknowledge.