In which position does a person lie on one side of their body?

The lateral position is when a person lies on their side, with one side of the body down. This positioning can be beneficial for a variety of clinical reasons, such as facilitating breathing by reducing airway obstruction and improving lung expansion in the dependent lung. It can also help prevent pressure sores in patients who are immobile for extended periods.

The supine position refers to lying on the back, while the prone position indicates lying face down. The sitting position involves a person being upright, which differs significantly from lying on one's side. Therefore, the lateral position is specifically defined by its orientation, making it the correct choice in this context.