Pathological examination, also known as histopathology, is a vital tool used by medical professionals to diagnose diseases. There are several different synonyms for pathological examination, including tissue biopsy, histology, and cytology. A tissue biopsy is a procedure where a small sample of tissue is removed from the body and examined under a microscope. Histology refers to the study of tissues and how they are organized in the body. Cytology, on the other hand, involves the examination of individual cells to diagnose diseases. Other related terms include immunohistochemistry, which involves the use of antibodies to analyze tissue samples, and electron microscopy, in which high-powered microscopes are used to study the structure of cells and tissues.