Trying to appear wise, intelligent, and important, in a way that is annoying.
An arrogant, annoying individual may have an inflated sense of self or present as rather egotistical. Perhaps he is bombastic, pretentious, puffed up, or even turgid. There are many ways to describe such a person. But why settle for such common terms when describing your petty lord, self-important scholar or bureaucrat, preening professor, or overconfident, er…space lawyer?
Just be careful when wielding this one, lest you yourself come across as sententious due to your deployment of overly difficult words.
The Refluxive made a half-obsequious, half-sardonic gesture. “Here we are; stare yourselves full at the dreadful ‘cult.’ Have you ever seen anything less obstreperous?”
“The ‘cult,’ said Helsse, somewhat sententiously, “is despised not for the look of its meeting halls, but for its provocative assumptions.”
“‘Assumptions’ bah!” declared the Refluxive in a voice of peevish complaint. “The others persecute us but we are the chosen in knowledge.”
– Jack Vance, Servants of the Wankh (1969)