partssides

Partssides is a term used in certain engineering, CAD, and manufacturing contexts to designate the distinct sides or faces of a part that are relevant for design, assembly, or verification. The word is a portmanteau of "parts" and "sides" and is not part of an official, standardized nomenclature.

Usage in practice varies, but partssides generally help map surfaces for tolerancing, surface finishing, or mating with other components. They may correspond to common categories such as left/right, top/bottom, or front/back, depending on the part’s orientation. In bill of materials and assembly instructions, references to specific partssides help indicate where features meet other components or how surfaces should be finished. The term is more common in some teams and vendors than in others, and many practitioners use alternate terms like faces or surfaces.

Designation often involves labeling with suffixes or letters to distinguish sides, such as P-1234-L or P-1234-R, to support automation in computer-aided manufacturing and enterprise resource planning workflows. Because practices vary by company, some teams avoid the term altogether in favor of more widely understood terminology to reduce ambiguity.

Advantages and limitations: Using partssides can improve clarity in complex assemblies and aid process automation, especially in CAD-to-manufacturing pipelines. However, the lack of universal standardization means the term may be unfamiliar to new engineers and can lead to misinterpretation if not accompanied by precise definitions and consistent labeling.

See also: Surface, Face (geometry), Mating surface, Interface, Bill of materials.