Final answer:
The nurse should use the term 'Catatonia' to describe the symptoms.
Step-by-step explanation:
The best term for the nurse to use to describe these symptoms is Catatonia. Catatonia is a neuropsychiatric syndrome characterized by a state of unresponsiveness and immobility. The individual may appear mute, show no movement, and be unaware of their surroundings. It can occur in various psychiatric and medical conditions, such as schizophrenia, mood disorders, and neurological disorders.