Product lifecycle management (PLM) is a strategic product-centric, lifecycle-oriented and information-driven business approach that strives to integrate people and their inherent practices, processes, and technologies, both within and across functional areas of the extended enterprise from inception to disposal. The integration of people relies on the harmonisation of domain-specific glossaries by standardising a universal PLM vocabulary. So far, unfortunately, there is no PLM standard vocabulary. Therefore, the tremendous amount of knowledge that is continually brought forward by academic research studies, industrial practices and computer-aided applications causes semantic ambiguities. This paper consists of an illustrated glossary and a conceptual map. The glossary identifies, discusses, clarifies and illustrates ambiguous terms used in discrete manufacturing. The conceptual map finally underlines the logical flow of refereed definitions.