hemat

Hemat is a combining form used in medical terminology to indicate a relation to blood. It derives from the Greek haima, meaning blood, and appears in a wide range of terms describing the biology, physiology, and pathology of the circulatory system and blood formation.

In English, spellings include hemat- (American usage) and haemat- or haem- (British usage). The prefixes haemato- and haemo- are also used in related compounds such as haemoglobin and haemopoiesis, linking to blood components and blood-forming processes.

Common terms built with hemat include hematology, the study of blood and blood-forming tissues; hematopoiesis, the production of blood cells; hematocrit, the proportion of blood volume occupied by red blood cells; hematoma, a localized collection of blood outside vessels; and hematemesis, the vomiting of blood.

Hemat is a productive prefix in medicine and biology, appearing in terms that describe blood components, diseases, and physiological processes. It should be noted that regional spelling differences (hemat- versus haemat- or haem-) reflect British versus American usage rather than a change in meaning.

See also: hematology, haemoglobin, hemostasis, hematopoiesis.