This Technical Specification specifies a reference dictionary for cutting items, together with their descriptive properties and domains of values, for use in cutting tool data representation. The reference dictionary contains definitions and identifications of the classes of cutting items and their features, with an associated classification scheme, definitions and identifications of the data element types that represent the properties of cutting items and their features, and definitions and identifications of domains of values for describing those data element types. Each class, property or domain of values of this application domain constitutes an entry of the reference dictionary defined in this Technical Specification. It is associated with a computer-sensible and human-readable definition, and with a computer-sensible identification. Identification of a dictionary entry allows unambiguous reference to it from any application that implements the information model defined in ISO 13399-1. Definitions and identifications of dictionary entries are defined by means of standard data that consist of instances of the EXPRESS entity data types defined in the common dictionary schema, resulting from a joint effort between ISO TC184/SC4/WG2 and IEC SC3D, and in its extensions defined in ISO 13584-24 and ISO 13584-25. The following are within the scope of this Technical Specification: standard data that represent the various classes of cutting items and cutting item features; standard data that represent the various properties of cutting items and cutting item features; standard data that represent domains of values used for properties of cutting items and cutting item features; definitions of reference systems for cutting items and their properties; one implementation method by which the standard data defined may be exchanged.