Dictionary.com
Thesaurus.com
Jump To:
  • hyper
    hyper
    adjective
    overexcited; overstimulated; keyed up.
  • hyper-
    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 ).
  • hyper–
    hyper–
    A prefix that means “excessive” or “excessively,” especially in medical terms like hypertension and hyperthyroidism.
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 ( see super-); akin to over

Explanation

Someone who's hyper is overly excited or energetic. If coffee and tea make you feel a little hyper, you might try switching to decaf! Hyper is a shortened form of hyperactive, a behavior that includes restlessness and sometimes inappropriate amounts of movement. It's part of an official diagnosis, attention deficit hyperactivity disorder, or ADHD. But hyper also describes any excessive activity or feeling or excitability: "I want one of these sleepy kittens, not those hyper ones climbing the curtains." The Greek root of hyper means "too much," and when someone is hyper, they really are too much!

Keep Reading on Vocabulary.com

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.

See Examples For:

“Right now, I’m still in hyper growth mode, even though I’m retired.”

From The Wall Street Journal ● Jul. 16, 2026

In total darkness and my senses hyper alert, any conversation we had bounced off the walls of what felt like a never-ending tunnel.

From BBC ● Jul. 11, 2026

"When we inactivate these neurons, the mice become hyper distractable," Kothari said.

From Science Daily ● Jun. 24, 2026

“Everyone’s hyper focused on the number of units,” Allman said.

From Los Angeles Times ● Jun. 10, 2026

And when I get close enough, his hyper butt jumps up my legs, nearly taking me down.

From "The Hate U Give" by Angie Thomas

After abandoning the Americana of their first few albums for something more personal, Rose has explored the many facets of pop, whether indie-, hyper- or otherwise.

From Washington Post ● Apr. 12, 2023

Almost all prokaryotes have a cell wall, a protective structure that allows them to survive in both hyper- and hypo-osmotic conditions.

From Textbooks ● Jun. 9, 2022

Funny, nobody sought to ban swimmer Michael Phelps for his naturally occurring hyper- and double-extended joints, longer-than-average torso and wingspan, or powerful lung capacity.

From New York Times ● Jul. 23, 2021

"This is not the stuff of hyper- or even double-digit inflation, but it is draining and seemingly one thing after another," he said.

From Los Angeles Times ● Jun. 17, 2014

Of course both in hypo- and in hyper- the vowel is short in Greek, so that here at least the strange lengthening cannot be ascribed to the Grecians.

From Society for Pure English Tract 4 The Pronunciation of English Words Derived from the Latin by John Sargeaunt

Vocabulary.com logo
by dictionary.com

Just like flashcards, but way more fun

Don't take our word for it. Leave the boring studying behind and join VocabTrainer today. You'll learn even faster and never look back.

Take me to Vocabulary.com