persistent vegetative state
From Longman Dictionary of Contemporary Englishpersistent vegetative stateperˌsistent ˈvegetative ˌstate noun [countable] medical a condition in which someone’s brain is so damaged that they cannot move or talk, and their condition is unlikely to improveExamples from the Corpuspersistent vegetative state• He had been in a persistent vegetative state since being crushed in the Hillsborough disaster on April 15,1989.