Which prefix is used to indicate something is below normal?

The prefix "hypo-" is used to indicate that something is below normal or below a certain level. This prefix comes from Greek, where it conveys the meaning of "under," "beneath," or "less than." In medical terminology, for example, "hypoglycemia" refers to a condition in which blood sugar levels are lower than normal, highlighting the usage of "hypo-" to denote a deficiency or subnormal condition. Therefore, when describing a state that is less than the typical or expected level, "hypo-" is the precise prefix to convey that meaning.

The other prefixes include "hyper-", which indicates above normal or excess, "endo-", which means within or inside, and "exo-", referring to outside or external. These distinctions help clarify the specific conditions being described in various contexts.