(~s)
1.
In Britain, a ~ is a senior police officer of the rank above an inspector. In the United States, a ~ is the head of a police department.
He was stopped at the airport by an assistant ~ of police.
...Detective Superintendent Kirby.
N-COUNT; N-TITLE
2.
A ~ is a person who is responsible for a particular thing or the work done in a particular department.
He became ~ of the bank’s East African branches...
N-COUNT: N of n
3.
A ~ is a person whose job is to look after a large building such as a school or a block of flats and deal with small repairs to it. (AM; in BRIT, use caretaker )
N-COUNT