Terms and Acronyms
KeyCreator \ Assemblies \ Overview \ Terms-and-Acronyms


The list below contains several key terms and acronyms that will need to be understood before using Assemblies during the design and organization of your files. Note that further explanations of these terms can be found throughout the Part Reference Options and Editing Referenced Parts segments.

Design File

The design file, or, .CKD file, can contain one or more parts.


A part is a uniquely specified component or assembly of components. See the section on Part Reference Options segment for expanded information. Part names cannot be more than 31 characters in length.

Host Part

A host part is one that contains part references to another part. Note that a host part can have multiple references to the same part.

Referenced Part

A referenced part is one that is referred to by a part reference in a host part.

Part Reference (PR)

A part reference is an entity that references an existing part, and is the same as an Instance, which you might see being referred to throughout this chapter. Entities from the part are not stored with the reference.


When a part reference is hidden, its visual representation is replaced with a bounding cuboid, which retains the color attribute of the hidden part reference.

Local Reference

A part reference is a local reference in a given host part if it is contained directly within that part.

Nested Reference

A "nested" reference is a non-local reference, and is a reference in a part that is referred to by another reference, from the tree’s point of view. In the PartRefs window (see Using the Interface), a line belonging to a nested reference is gray – where the line belonging to a local reference is white.


When you suppress a part reference, it is not only hidden from view – the entities belonging to the suppressed part reference are "removed" from the part.

Part Reference Entities (PRE)

Display entities placed in the graphics system to represent the referenced geometry. These are not entities in the database.


An Instance and a Part Reference are identical.

In-Context Editing

The editing of a part while it is displayed in the context of an assembly. All other geometry in the displayed part is available to be used as reference geometry while the edit is being performed. Such editing is done through a single instance (see above) of that part. Any other instances containing references to that same part will behave normally.

Active Part

This is the part being edited within a window. For any window, this begins as the Displayed Part.

Displayed Part

This is the part that is normally active in the window where the editing occurs. The Displayed Part contains a reference (either directly or indirectly) to the Active Part (part being edited).


Lightweight is similar to "Suppressed" mode in that the full geometric data of the referenced part is not loaded in memory. Instead, a lightweight stream is loaded and displayed. This allows visualization of the reference model, without the overhead of the full geometric data. See Lightweight for more details.