जखम, कापणे, रोग,शस्त्रक्रिया, शिकारी पशुंचा हल्ला इत्यादींसारख्या घटनांमुळे प्राण्यांच्या शरीरातुन रक्त बाहेर निघण्याची क्रिया.

Bleeding, hemorrhage, haemorrhage or blood loss is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination. Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties. The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery.