Which term describes a position where a person is lying face down?

The term that describes a position where a person is lying face down is "prone." In medical terminology, "prone" specifically indicates that the individual is horizontally positioned with their chest and abdomen facing the ground. This position is often used in various medical assessments and treatments, such as during certain surgical procedures or for assessing back injuries.

In contrast, "supine" refers to lying on the back, "lateral" describes a position lying on one side, and "vertical" indicates an upright position. Recognizing these specific terms is crucial for effective communication in emergency medical situations, where precise descriptions of body positions can greatly impact patient care and assessment.