Several types defined in Clause [input.output] are enumerated types. Each enumerated type may be implemented as an enumeration or as a synonym for an enumeration.167
The enumerated type enumerated can be written:
enum enumerated { V0, V1, V2, V3, ..... }; static const enumerated C0 (V0); static const enumerated C1 (V1); static const enumerated C2 (V2); static const enumerated C3 (V3); .....
Here, the names C0, C1, etc. represent enumerated elements for this particular enumerated type. All such elements have distinct values.
Such as an integer type, with constant integer values ([basic.fundamental]).