Adjective

1. Overbearingly arrogant; ostentatiously self-important or self-aggrandizing.

   Ever since she was placed in the gifted program, she's become so high and mighty that no one wants to be near her.

Noun

1. A social or economic group wielding undue power, influence or economic clout.

   The Fairlawn Country Club is the watering hole for the city's high and mighty.