noun
telephone exchange; switching center
Refers to a facility that connects telephone calls; a technical term in telecommunications.
昔は交換局のオペレーターが手動で電話をつないでいた。
In the past, operators at the telephone exchange manually connected calls.
noun
postal exchange; international mail exchange
A facility that handles international mail, including customs clearance. Often used in the context of 国際郵便交換局.
国際郵便交換局で通関手続きが行われる。
Customs clearance is carried out at the international postal exchange.