(~s)
1.
In Britain and some other countries, a ~ is a police officer of the lowest rank.
He was a ~ at Sutton police station.
...Constable Stuart Clark...
Thanks for your help, Constable.
N-COUNT; N-TITLE; N-VOC
see also Chief Constable
2.
In the United States, a ~ is an official who helps keep the peace in a town. They are lower in rank than a sheriff.
N-COUNT; N-TITLE