What is the term for the position of lying flat on the back, face upward?

The term that describes the position of lying flat on the back, face upward, is "supine." In this position, the individual is resting on their back with their face directed upward towards the ceiling or sky. This is a commonly used term in medical and health contexts, as the supine position is often utilized during various assessments, procedures, and treatments, such as cardiac monitoring or abdominal examinations.

Prone refers to lying on one’s stomach, which is the opposite of supine. Supination is a term usually associated with the rotational movement of the forearm or foot, not a body position. Sitting, while a common position, does not describe lying down flat and is therefore unrelated to the question. Understanding these terms is crucial for clarity in medical situations, as positioning can significantly affect patient care.