Originally, it means "indentation" (ex. Dimple of a golf ball). However, in the case of connectors, although it is a little complicated, the structure that has a dimple on the back of the contact side of the terminal and a protrusion on the contact side that stabilizes the contact is called a "dimple contact", a "dimple structure", or simply a "dimple". There is a thing called, and it is established. We mainly use it for this content in our page.