What is the name of the element in the network that, when activated, disconnects it?

Question

Electronics

For example: there is a wire - in the middle of it is a button that, when pressed, disconnects the phase. As soon as the button is released, the phase is connected again. What is this (device? element? button?) called?

Answer 1

Pushbutton with normally closed contacts without latching

Answer 2

Also sometimes called "opener".