ˌplain-ˈclothes adjective [only before noun]
plain-clothes police are police who wear ordinary clothes so that they can work without being recognized

[TahlilGaran] Dictionary of Contemporary English ▲

police officer (also officer) a member of the police. In British English, police officer is used especially in more formal contexts, for example in news reports. In everyday English, British people still usually say policeman or policewoman:
a senior police officer
He was sentenced to life in prison for killing a police officer.
He is the officer in charge of the case.
Officer Fayard (=in the US ‘Officer’ is used in the title of police officers)
policeman a man who is a member of the police:
an off-duty policeman
He’s a former policeman.
policewoman a woman who is a member of the police:
The girl, accompanied by a policewoman and two social workers, was seen in private by Sheriff George Crozier.
PC/WPC abbreviation used in the job titles of British police offiicers. PC means ‘Police Constable’ and WPC means 'Woman Police Constable':
PC Keith Fletcher
WPC Susan Larkin
detective a police officer whose job is to discover who is responsible for crimes:
Detectives are investigating the death of a baby boy.
Detective Inspector John Hartwell
plain-clothes adjective a plain-clothes police officer wears ordinary clothes instead of a uniform:
Two plain-clothes police officers, acting as hotel security men, kept watch on him.
constable a British police officer of the lowest rank:
a police constable
Constable Robin Cameron
chief constable a senior police officer who is in charge of the police in a particular area in Britain:
the chief constable of North Yorkshire police
cop informal a police officer:
You’d better call the cops.
trooper a US police officer in a state police force:
a New Jersey state trooper

[TahlilGaran] English Thesaurus ▲