What does the prefix "sub-" specifically refer to in medical vocabulary?

The prefix "sub-" in medical vocabulary is derived from Latin, meaning "under" or "below." This prefix is commonly used in various medical terms to indicate a position that is beneath or less than something else. For instance, "subcutaneous" refers to the layer of tissue beneath the skin, and "subnormal" indicates values that are below what is considered normal.

Understanding this prefix is essential as it helps in interpreting a wide range of medical terminology, allowing healthcare professionals to accurately describe anatomical locations, conditions, or the relationship between different structures in the body.