Definition: A collection of parts (or assemblies or features) that are essentially similar, but deviate slightly in one or two aspects, such as size or detail features. For example, wood screws come in various sizes, but they all look alike and perform the same function. Thus, it is useful to think of them as a family of parts. Parts in Family Tables are also known as table-driven parts.

Citation: PTC : PTC Fundamentals, MBD, and Assembly Glossaries