Which term refers to tissue death due to a lack of blood supply?

The term that refers to tissue death due to a lack of blood supply is "infarct." When blood supply is cut off from a particular area of tissue, the tissue can become ischemic and eventually die, leading to the formation of an infarct. This process commonly occurs in various organs, such as the heart or brain, resulting in serious medical conditions like myocardial infarction (heart attack) or cerebral infarction (stroke).

The other terms mentioned are distinct medical terms with specific meanings. For instance, odynophagia refers to painful swallowing, lymphadenopathy is the enlargement of lymph nodes often due to infection or disease, and orthopnea is a medical condition where a person experiences difficulty breathing when lying flat. These terms do not relate to tissue death or lack of blood supply, emphasizing why "infarct" is the correct choice.