noun, noun which may take the genitive case particle 'no'
ordinary clothes; plain clothes; casual wear
Clothes worn instead of a uniform, especially in contrast with 制服. Used as a noun and in の-modifying phrases such as 私服の学生.
See also: 制服
明日は制服ではなく私服で来てください。
Please come in ordinary clothes tomorrow, not in uniform.
その高校
That high school allows students to come to school in their own clothes.
noun
Abbreviation of 私服刑事 or 私服警官. Used in police, crime-reporting, or fiction contexts for an officer not wearing a uniform.
See also: 私服刑事
容疑者を私服が尾行した。
A plainclothes officer tailed the suspect.
The full expression for a plainclothes detective; 私服 alone can be used as its abbreviation in context.
A Sino-Japanese compound of 私, associated with private or personal matters, and 服, clothing. The spelling transparently contrasts with 制服, a uniform.