MetaObjectProtocol (aka. MOP)

Is a standard to define the (dynamic) behaviour of the MetaClasses? that establish the CommonLispObjectSystem. This includes the creation, modification and instantiation of classes, Objects (instances) and Methods.

see e.g.:

• ​http://www.lisp.org/mop/index.html
• ​http://en.wikipedia.org/wiki/Meta-object_protocol