Legal Writing

Hyper and Hypo

By Simon Kewin

Be careful with hyper- and hypo-.

These two prefixes are easily confused as they sound so similar but they have, in fact, more-or-less opposite meanings.

Hyper- means over, excessive, more than normal, as in such words as hyperbole (extravagant and obvious exaggeration) and hyperactive (abnormally or pathologically active). The prefix derives from the Greek word hyper, meaning simply over.

Hypo-, on the other hand, means under, defective or inadequate, as in such words as hypodermic (under the skin) or hypoallergenic (specially formulated to minimize the risk of an allergic reaction). This, too, derives from the Greek : hypo, meaning under.

These prefixes are often used in a medical context, and confusion can arise because different conditions can have such similar sounding names. For example, hyperthyroidism (the over-production of thyroid hormones) doesn?t sound too different to hypothyroidism (the under-production of these hormones). Similarly, hypertension refers to high blood pressure whereas hypotension means the opposite : low blood pressure. Hyperglycaemia refers to abnormally high blood-sugar levels whilst hypoglycaemia means abnormally low levels, and so forth.

In whatever context you?re using hyper- and hypo- words, it makes sense to be very clear about which prefix is the correct one to use.

Full post as published by Daily Writing Tips on July 17, 2010 (boomark / email).