Which prefix means “many” or “more than once”?

The prefix that means “many” or “more than once” is "poly-." This prefix is derived from the Greek word "polus," meaning "many" or "much." It is commonly used in medical terminology to describe conditions involving multiple elements, such as "polycythemia," which refers to an increased number of red blood cells, or "polydipsia," indicating excessive thirst.

"Multi-" is also a prefix that means "many" but is generally used in a broader context and does not specifically imply repetition in the same way "poly-" does.

"Tetra-" refers to four, indicating a specific number rather than a quantity of many, while "dual-" indicates two, which does not correspond to the concept of many or repetition either.

Understanding the nuances of these prefixes enhances comprehension across various medical terms and their implications.