Chief is used in the job titles of the most senior worker or workers of a particular kind in an organization.
head , senior
the chief test pilot.
首席试飞员。
He rose up through the ranks to become chief engineer.
他不断晋升,成为了总工程师。
The chief cause, part, or member of something is the most important one.
main , major , key , principal
minor , unimportant
Financial stress is well established as a chief reason for divorce.
经济压力被充分证实为导致离婚的一个首要因素。
The job went to one of his chief rivals.
他的一个主要对手得到了这份工作。
chiefs
The chief of an organization is the person who is in charge of it.
a commission appointed by the police chief.
由警察局长挑选人员组成的委员会。
The chief of a tribe is its leader.
Sitting Bull, chief of the Sioux tribes of the Great Plains.
大平原苏人部落的首领西延·布尔。