xyy syndromeglossary / XYY SYNDROME XYY syndrome. The abnormal presence of an extra Y chromosome in a male, theoretically resulting in increased aggressiveness and antisocial behavior often resulting in criminal conduct. 词条贡献者 译员Jerry,知名法学院知识产权法,专注翻译各种与版权与商标诉讼有关的法律文件。