What prefix would describe a deficiency in a medical context?

The prefix that describes a deficiency in a medical context is "hypo." This prefix is derived from Greek, meaning "under" or "below normal." It is commonly used in various medical terms to indicate that something is present in insufficient amounts or is lacking. For instance, "hypoglycemia" refers to lower than normal levels of glucose in the blood, and "hypotension" denotes lower than normal blood pressure.

Using this understanding, the other prefixes do not convey the idea of deficiency. "Hyper" suggests an excess or above normal level, "pre" indicates something that occurs before, and "epi" means upon or above. These meanings contrast with the idea of deficiency that "hypo" communicates.