What does the prefix "intra" signify in medical terminology?

The prefix "intra" in medical terminology signifies "inside" or "within." This prefix is commonly used to describe locations or actions that occur within a structure or organism. For example, the term "intravenous" refers to something occurring within a vein, while "intrapersonal" relates to thoughts or feelings that occur within an individual.

In contrast, the other options represent different meanings that do not align with the definition of "intra." The meanings associated with those terms, such as "outside, beyond," "below, under," and "between," all signify different relationships or locations that do not encapsulate the idea of being contained or occurring within something. Therefore, "inside, within" perfectly describes what the prefix "intra" conveys in medical terminology.