Which term is used to describe a person lying down on their stomach?

The term that describes a person lying down on their stomach is “prone.” This position involves the person facing downwards, which can be significant in various medical situations. Being in the prone position can help with certain types of respiratory distress or can be utilized during specific medical examinations or treatments.

The term "supine" refers to lying on one’s back, which is the opposite of prone. "Fowler's" describes a seated position where the individual’s back is elevated, facilitating easier breathing or comfort in certain medical assessments. "Proximal" is an anatomical term that describes a position closer to the center of the body or point of attachment, not related to body positioning in terms of lying down. This makes "prone" the correct answer in the context of the question.