arrogant
Definitions
Having or revealing an exaggerated sense of one's own importance or abilities.
Overbearingly assuming; insolently proud.
Examples
His arrogant attitude made it difficult for him to make friends at the new office.
It was arrogant of him to assume that he was the only person qualified for the promotion.
Synonyms
haughty conceited pompous supercilious egotistical snobbish overbearing