Medical laboratories are perhaps the largest measurement industry in the world. The metrology terminology is relevant for effective and efficient communication, particularly where metrology activities are carried out by operators with different metrology skills. WASPaLM and SIPMeL have had some opportunities to propose changes to the documents in preparation to CLSI and ISO in order to harmonise the terminology with the Metrology Vocabulary (VIM). Many proposals have been accepted. Here we summarise some particularly critical points for metrological terms. The main terms discussed are: Measuring, measuring range, examination, pre-examination, post-examination, manufacturer, measuring instrument, quantitative, qualitative, semi-quantitative, processing, easurement error, maximum permissible error of measurement, total error of measurement, monitoring, variability, performance, reliability, influence, interference, selectivity, sensitivity, detection limit, reliability, pomparability, compatibility, control material. Despite all efforts to coordinate terminologies, it is inevitable that overlapping and inconsistent terminologies will continue to be used because documents and policies are produced in different contexts. In some ISO and CLSI documents, phenomena of magnetic attraction towards common words (such as “analysis” and derivatives), without any consideration of the true metrological meaning, are noted. The ISO and CLSI working groups show, alongside moments of openness, phenomena of true self-referential conservatism.