The term for blood discoloration of the tissues, often resulting in a bruise, is ecchymosis. This condition occurs when blood vessels are damaged and blood leaks into the surrounding tissues, leading to the characteristic blue or purple marks commonly associated with bruising. Ecchymosis is larger than petechiae, which are tiny pinpoint spots, and typically appears as a more pronounced area of discoloration.
In contrast, an infarct refers to an area of tissue that has died due to lack of blood supply, while a vesicle is a small fluid-filled blister that can develop on the skin. An abscess is a localized collection of pus that can occur in various tissues of the body, usually as a result of infection. Understanding these terms helps clarify the specific nature of ecchymosis in the broader context of tissue responses to injury and blood vessel integrity.