妄自尊大

- be overbearing; aggrandize oneself; be arrogant and overweening; be eaten up with pride; be given to swaggering; be overweening; be puffed up with pride; be puffed up with self-importance; be self-conceited [self-important]; boast wildly of oneself; give oneself airs; have too high an opinion of oneself; indulge in foolish display; self-conceit; self-glorification; self-importance; set oneself up as superior to everyone; swell with pride; think no small beer of oneself