A biopsy is a medical procedure in which a sample of tissue is taken from the body for examination. It is usually done to diagnose a disease or to determine the cause of an illness. The term 'biopsy' comes from the Greek words 'bios' meaning 'LIFE' and 'opsis' meaning 'VIEW'. A tissue sample taken during a biopsy is used to examine the cells and tissues of the body, allowing doctors to make a diagnosis.