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hyper-

a prefix appearing in loanwords from Greek, where it meant “over,” usually implying excess or exaggeration (hyperbole); on this model used, especially as opposed to hypo-, in the formation of compound words (hyperthyroid).
Compare super-.

Origin of hyper-

Greek, representing hypér over, above; cognate with Latin super (see super-); akin to over
Can be confusedhyper- hypo-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for hyper-

hyper-

prefix

above, over, or in excesshypercritical
(in medicine) denoting an abnormal excesshyperacidity
indicating that a chemical compound contains a greater than usual amount of an elementhyperoxide

Word Origin for hyper-

from Greek huper over
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for hyper-

word-forming element meaning "over, above, beyond, exceedingly, to excess," from Greek hyper (prep. and adv.) "over, beyond, overmuch, above measure," from PIE super- "over" (see super-).

Online Etymology Dictionary, © 2010 Douglas Harper
hyper- in Medicine

hyper-

pref.

Over; above; beyond:hyperflexion.
Excessive; excessively:hyperhydration.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
hyper- in Science

hyper-

A prefix that means “excessive” or “excessively,” especially in medical terms like hypertension and hyperthyroidism.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.