Hypoactive

Part of speech: adjective

Definitions

1. Exhibiting activity below the typical level expected in a person or system
2. Showing reduced or diminished action compared to the usual or expected norm
3. Characterized by lower than normal activity or responsiveness in a biological or functional context

Etymology: Hypoactive is a plain compound: the Greek prefix "hypo-", meaning "under" or "below", attached to "active". The result describes something running below its normal level of activity, which is why the word is most often applied to the body. A hypoactive thyroid, for instance, produces less of its hormone than it should. The prefix does the real work here. "Hypo-" shows up in many scientific coinages, usually signalling a deficiency or a position beneath something else, so hypoactive belongs to the same family as hypotension, meaning low blood pressure, and hypothermia, meaning abnormally low body temperature. Each takes a familiar stem and adds the sense of falling short of a norm. Because "active" can describe anything from a volcano to a bank account, hypoactive is used across medicine and psychology as well as in everyday talk about people or systems that seem sluggish or unresponsive.

Synonyms: underactive, sluggish

Antonyms: hyperactive