histologyPronunciation: /hɪˈstɒlədʒi/Definition of histology noun [mass noun] Biology the study of the microscopic structure of tissues. Derivatives histologic adjective histologicalPronunciation: /hɪstəˈlɒdʒɪk(ə)l/ adjective histologistPronunciation: /hɪˈstɒlədʒɪst/ noun histology in other Oxford dictionaries Definition of histology in the US English dictionary