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Synonyms

hyper

1 American  
[hahy-per] / ˈhaɪ pər /

adjective

  1. overexcited; overstimulated; keyed up.

  2. seriously or obsessively concerned; fanatical; rabid.

    She's hyper about noise pollution.

  3. hyperactive.

noun

  1. a person who is hyper.

hyper 2 American  
[hahy-per] / ˈhaɪ pər /

noun

Informal.

  1. a person who promotes or publicizes events, people, etc., especially one who uses flamboyant or questionable methods; promoter; publicist.

hyper- 3 American  

  1. 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 ).

hyper- 1 British  

prefix

  1. above, over, or in excess

    hypercritical

  2. (in medicine) denoting an abnormal excess

    hyperacidity

  3. indicating that a chemical compound contains a greater than usual amount of an element

    hyperoxide
"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
hyper 2 British  
/ ˈhaɪpə /

adjective

  1. informal overactive; overexcited

"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
hyper– Scientific  

  1. A prefix that means “excessive” or “excessively,” especially in medical terms like hypertension and hyperthyroidism.

Etymology

Origin of hyper1

First recorded in 1970–75; probably independent use of hyper-

Origin of hyper2

1910–15, for an earlier sense; hype 1 + -er 1

Origin of hyper-3

Greek, representing hypér over, above; cognate with Latin super ( super- ); akin to over

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In this room, I am at times unsettled, at once tracking the movements of the actors while attempting to remain hyper aware of any sudden touch or scent.

From Los Angeles Times • Mar. 26, 2026

While the subject matter is drawn from traditional Japanese art and the other materials are ancient in their legacy, these quiet meditations are hyper contemporary.

From The Wall Street Journal • Feb. 27, 2026

When the Sun gets all hyper with magnetic activity, it throws out huge bursts of super-hot, super-fast gas called plasma.

From Space Scoop • Nov. 19, 2025

“After some years of hyper growth, then we’ve seen deceleration of growth rates for the company,” Novo CFO Karsten Munk Knudsen told Barron’s.

From Barron's • Nov. 6, 2025

Via was kneeling down in front of the dog, trying to pet it, but the dog was kind of hyper and kept trying to lick her hand, which Via kept pulling away.

From "Auggie & Me" by R. J. Palacio

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.