Hypo-

When I came across the English word hypoxia, I thought the prefix hypo- must indicate something bad or false, judging from the words such as hypothesis and hypocrisy. However, it was not quite right.

This prefix hypo- comes from the Ancient Greek ῠ̔πό (hupó) that basically means “under, near”. Thus, the word hypothesis does make sense since a hypothesis is still “under thesis”. The crisy part in hypocrisy comes from κρῑ́νω (krī́nō), meaning “to distinguish”¹. Although I tried to explain this somehow, I couldn’t really figure out how it came to mean “pretense”. Hypoxia means “deficiency of oxygen in the tissues”.

Some more medical (yet commonly used) terms are easy to understand; the term hypotension means “low blood pressure” and hypothalamus (視床下部) is a region of the forebrain located below the thalamus (視床) (where 下 here means “under”).