chief
adjective
uk/tʃiːf/ usbiggest or most important; main:
Our chief concern right now is getting all these goods out onto the shelves.
Coffee and rice are the country's chief exports.
highest in rank:
the chief accountant/security officer
chief
noun [ C ]
uk/tʃiːf/ usa person who is in charge of a group or organization:
a police/fire chief
the chief of police