What medical term describes a localized area of dead tissue?

The term that describes a localized area of dead tissue is "infarct." An infarct occurs when blood flow to a particular area is restricted or blocked, usually due to a clot or other obstruction, leading to the death of the tissue in that specific area because it is deprived of oxygen and nutrients. This process is often seen in conditions like heart attacks or strokes, where the tissue affected relies on a steady supply of blood.

In contrast, other terms provided refer to different medical conditions. An abscess is a collection of pus that forms as a result of infection and contains dead tissue and bacteria, rather than simply being defined as dead tissue. A cyst is a sac-like structure that can be filled with fluid, air, or other material, and does not specifically denote dead tissue. A hematoma refers to a localized collection of blood outside of blood vessels, usually due to injury, which is not the same as localized dead tissue.