What does the prefix "hypo-" refer to?

The prefix "hypo-" is utilized in medical terminology to indicate a deficiency or a level that is below what is considered normal or expected. This prefix is commonly used when describing conditions or states that fall short of standard measurements, such as "hypoglycemia," which refers to abnormally low levels of glucose in the blood. Therefore, within the context of the question, "below" captures the essence of what "hypo-" signifies in a medical setting.

The other prefixes like "above," which would be represented by "hyper-," and "before," referring to "pre-," or "around," indicated by "peri-," do not relate to the idea of deficiency or a state below normal. Each prefix has its own specific meaning and application; understanding these distinctions is crucial for accurate communication in the medical field.