The hallmark of something or someone is their most typical quality or feature.
例句
It's a technique that has become the hallmark of Amber Films...这已经成为安伯电影公司的标志性技术。The killing had the hallmarks of a professional assassination...这起谋杀案具有职业暗杀的特征。
N-COUNT
(金、银、铂制品上标明纯度、产地、制造者的)印记
A hallmark is an official mark put on things made of gold, silver, or platinum that indicates the quality of the metal, where the object was made, and who made it.