metrologyPronunciation: /mɪˈtrɒlədʒi/Definition of metrology noun [mass noun] the scientific study of measurement. Derivatives metrologicalPronunciation: /mɛtrəˈlɒdʒɪk(ə)l/ adjective metrologist noun Origin: early 19th century: from Greek metron 'measure' + -logymetrology in other Oxford dictionaries Definition of metrology in the US English dictionary