Chamfer

A chamfer with a "lark's tongue" finish

A chamfer (/ˈʃæmfər/ SHAM-fər or /ˈæmfər/ CHAM-fər) is a transitional edge between two faces of an object. Sometimes defined as a form of bevel, it is often created at a 45° angle between two adjoining right-angled faces.

Chamfers are frequently used in machining, carpentry, furniture, concrete formwork, mirrors, and to facilitate assembly of many mechanical engineering designs.