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conceit; vanity; pride; self-importance; egotism
彼は自分の才能を己惚れていて周りが見えていない。
He is so conceited about his talent that he cannot see others.
少しの成功で己惚れるのは危険だと先輩に言われた。
My senior told me it is dangerous to become conceited from a little success.
己惚れの強い人とは一緒に仕事をしたくない。
I do not want to work with someone who is very conceited.