IPA: /ˌhɪstəˈpæθəˌlɒdʒi/
KK: /hɪstəˌpæθəˈlɑdʒi/
The study of changes in tissues that occur due to disease, often examined under a microscope.
The doctor reviewed the histopathology to understand the nature of the disease.
Histopathology is formed from "histo-" (from Greek "histos", meaning tissue) and "pathology" (from Greek "pathologia", meaning the study of suffering or disease). The word refers to the study of tissue in relation to disease.
Think of 'tissue' ('histo-') being studied for 'disease' ('pathology') — that's what histopathology means.