What is the medical term for a localized irritation or area of tissue death?

The term "infarct" refers specifically to an area of tissue that has undergone localized death due to a lack of blood supply, often caused by an obstruction in the blood vessels. This condition can occur in various organs, including the heart (myocardial infarction) and brain (cerebral infarction), and is often associated with conditions such as heart attacks or strokes. Understanding this term is crucial in medical contexts, as it helps in diagnosing and determining the appropriate treatment for conditions related to ischemia (reduced blood supply).

The other terms do not pertain to localized tissue death. A keloid is a type of raised scar that forms due to excessive collagen production during healing, while "joint" refers to the area where two bones meet and is unrelated to tissue death. Lethargy describes a state of sluggishness or lack of energy, which does not relate to tissue irritation or necrosis.