What does the prefix "hypo-" mean?

The prefix "hypo-" is derived from Greek, meaning "under" or "below." In medical terminology, it is commonly used to describe a condition or status that is below normal levels. For instance, when discussing "hypoglycemia," it refers to lower than normal blood sugar levels. This prefix indicates a deficiency or decrease in the specified substance or function.

In contrast, the other choices represent different meanings: "increased" would imply a higher level; "vein" relates to the circulatory system; and "breast" pertains to mammary tissue. Understanding these prefixes can significantly aid in interpreting medical terminology effectively, emphasizing the importance of recognizing that "hypo-" indicates a decreased condition or function.