noun
crossbar switchboard
A type of telephone exchange that uses a matrix of horizontal and vertical bars to connect circuits. Technical term used in telecommunications engineering.
クロスバー交換機は、かつて電話局で広く使われていた。
Crossbar switchboards were once widely used in telephone exchanges.
Compound of クロスバー (crossbar) and 交換機 (switchboard/exchange), a direct calque of the English term.