Final answer:
The medical term decubitus means lying down or reclining. In the context of a chest x-ray, it refers to the lateral decubitus position where the patient lies on their side.
Step-by-step explanation:
The medical term decubitus refers to the position of lying down. The root word cubitus pertains to lying down or reclining. In the context of a chest x-ray taken in the lateral decubitus position, it means the patient is lying on their side to capture a specific view of the chest.
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