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plain clothes

American  
Or plainclothes

plural noun

  1. clothing other than one's uniform, especially civilian clothes worn on duty by a police officer.


plain clothes British  

plural noun

    1. ordinary clothes, as distinguished from uniform, as worn by a police detective on duty

    2. ( as modifier )

      a plain-clothes policeman

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • plain-clothes adjective
  • plainclothes adjective

Etymology

Origin of plain clothes

First recorded in 1815–25

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

They shouldn’t wear plain clothes but uniforms that identify their agency.

From The Wall Street Journal • Feb. 3, 2026

An M23 official confirmed to AFP Thursday that "police and soldiers in plain clothes" were still in Uvira as well as "our intelligence services".

From Barron's • Dec. 18, 2025

In some cases, the men wore plain clothes and refused to identify themselves.

From Salon • Oct. 24, 2025

A female police officer who volunteered to run in plain clothes to catch catcallers has said their behaviour "makes me feel really sort of icky".

From BBC • Aug. 15, 2025

She looked past the stocky man in plain clothes and saw ten— maybe more—cops lined up behind him.

From "The Other Wes Moore: One Name, Two Fates" by Wes Moore