plainclothesman has definitions from the field of law
1
[ noun ] (law) a detective who wears civilian clothes on duty

Used in print

(Richard S. Prather, "The Bawdy Beautiful," Cavalier...)

Two uniformed officers , a_couple_of plain-clothesmen I knew , and two other men stood on a gray cement area next to the pool on my left .

Lieutenant_Rawlins , one of the plain-clothesmen , spotted me and said , `` Hi , Shell '' , and walked toward me .

Related terms

detective

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