The Collaborative International Dictionary of English v.0.48:

Infarct \In*farct"\, n. [See Infarce.]
   1. (Med.) An obstruction or embolus in one of the blood
      vessels.
      [Webster 1913 Suppl.]

   2. (Med.) The morbid condition of a limited area resulting
      from such obstruction; also, the localized necrotic (dead)
      tissue resulting from such obstruction; as, a hemorrhagic
      infarct.
      [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

infarct
    n 1: localized necrosis resulting from obstruction of the blood
         supply [syn: infarct, infarction]