Which prefix means "under" or "below"?

The prefix "infra-" originates from Latin, where it means "under" or "below." It is commonly used in various scientific and medical terms to denote something that exists beneath or is lesser than a specified point or standard. For instance, "infrastructure" refers to the fundamental framework or systems that support a structure, often located beneath ground level. Similarly, in anatomy, "infrapatellar" refers to a location that is situated below the patella (kneecap).

In contrast, the other prefixes have different meanings: "intra-" means "within" or "inside," often used in terms like "intravenous," referring to something that occurs within a vein. "Ecto-" means "outside" or "external," used in terms like "ectoderm," which refers to the outer layer of cells in an embryo. "Inter-" means "between" or "among," as seen in terms like "interstate," which relates to things that exist or occur between states. Understanding these distinctions helps clarify the specific contexts in which each prefix is appropriately used.