1. （英国国王或女王授予的）爵士头衔，骑士头衔，爵士称号，骑士称号（其名前冠以Sir）
A knighthood is a title that is given to a man by a British king or queen for his achievements or his service to his country. A man who has been given a knighthood can put 'Sir' in front of his name instead of 'Mr'.

1. aristocrats holding the rank of knight