What term describes the state of being unaware and unresponsive to one's surroundings?

The term that describes the state of being unaware and unresponsive to one's surroundings is "coma." A coma is a medical condition characterized by a prolonged state of unconsciousness in which an individual does not react to external stimuli and lacks awareness of their environment. This results from various factors, such as severe brain injury, metabolic imbalances, or specific medical conditions.

While "unconscious" also refers to a lack of awareness, it is a broader term that can apply to various states ranging from light sedation to deep coma. "Dead" indicates a complete cessation of all biological functions and is not comparable to the state of being in a coma. The term "quadra," though not a standard medical term, does not relate to the state of unresponsiveness to surroundings and does not fit the context of this question. Thus, "coma" is the most appropriate description of a profound state of unresponsiveness.