親おや子こ電でん話わ

noun

extension phone (and its main line)

Refers to a pair of phones consisting of a main line and one or more extension handsets, often used in a home or small office. The term emphasizes the parent-child relationship between the main unit and its extensions.

• 親おや子こ電でん話わをリビングと寝しん室しつに設せっ置ちした。

  I installed an extension phone in the living room and bedroom.

• 親おや子こ電でん話わの子こ機きが故こ障しょうしたので、新あたらしいのを買かった。

  The extension handset of the parent-child phone broke, so I bought a new one.