The term "kidney shrinkage", which is used in both pathological anatomy and clinical contexts, is not uniformly defined. In medicolegal practice, it is particularly important whether or not a cause of death can be inferred from this diagnosis. If this were the case, a shrunken kidney determined in a forensic autopsy would obtain the same significance as a competing cause of death. International medical journals and German-language textbooks were searched for definitions of the various terms used to denote this condition, and the definitions were reassessed. The term "kidney shrinkage" was found to have historical roots and has further evolved since the 19th century. Although the first use of the term could not be determined with certainty, Bright (1789-1858) appears to be one of the first to use it in describing kidney disease. Definitions given in modern textbooks are based on kidney function, size, or macromorphology. However, these definitions lack uniformity and are often unsubstantiated. Because of its evocative power, the use of the historically coined term "kidney shrinkage" appears justified, at least as part of the medicolegal practitioner's jargon, to describe kidneys that have an uneven surface, decreased renal parenchyma, and a weight of less than 80 g, even if the term does not allow deductions about the degree of renal insufficiency and, thus, the significance of kidney shrinkage as the cause of death. The evaluation of such aspects requires histological analysis or referral to the results of clinical chemistry analyses that may have been performed while the individual was still alive.