What does the prefix "sub-" signify in anatomical terminology?

The prefix "sub-" in anatomical terminology signifies "below" or "under." This prefix is commonly used to describe structures that are positioned beneath another structure in the body. For instance, in terms such as "subclavian" (referring to the artery that runs beneath the clavicle) and "subcutaneous" (indicating the layer of tissue located under the skin), the prefix appropriately conveys the position relative to other anatomical landmarks.

Understanding this prefix is crucial in anatomy, as it helps to accurately describe the locations and relationships of various structures within the body.