arrogant       
adjective uk/ˈær.ə.ɡənt/ us/ˈer-/
B2 傲慢的;狂妄自大的;趾高气扬的
unpleasantly proud and behaving as if you are more important than, or know more than, other people
  I found him arrogant and rude. 我觉得他这个人狂妄自大、粗鲁无礼。 
 - More examples
 - She has an authoritative manner that at times is almost arrogant.
 - I watched the interview and thought he seemed quite arrogant.
 - He manages to exude confidence without being arrogant.
 - Like a lot of hospital consultants, he terrifies his patients with his arrogant manner.
 - If I say I'm a leading economic expert, won't that sound rather arrogant?