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definitions

freak-out

or freak·out

[freek-out]
See more synonyms for freak-out on Thesaurus.com
noun Slang.
  1. an act or instance of freaking out.
  2. a person who freaks out.

Origin of freak-out

First recorded in 1965–70; noun use of verb phrase freak out

freak

1
[freek]
noun
  1. any abnormal phenomenon or product or unusual object; anomaly; aberration.
  2. a person or animal on exhibition as an example of a strange deviation from nature; monster.
  3. a sudden and apparently causeless change or turn of events, the mind, etc.; an apparently capricious notion, occurrence, etc.: That kind of sudden storm is a freak.
  4. Numismatics. an imperfect coin, undetected at the mint and put into circulation.
  5. Philately. a stamp differing from others of the same printing because of creases, dirty engraving plates, etc.Compare error(def 8), variety(def 8).
  6. Slang.
    1. a person who has withdrawn from normal, rational behavior and activities to pursue one interest or obsession: a drug freak.
    2. a devoted fan or follower; enthusiast: a baseball freak.
    3. a hippie.
  7. Archaic. capriciousness; whimsicality.
adjective
  1. unusual; odd; irregular: a freak epidemic.
verb (used with or without object)
  1. to become or make frightened, nervous, or wildly excited: The loud noise caused the horse to freak.
Verb Phrases
  1. freak out, Slang.
    1. to enter into or cause a period of irrational behavior or emotional instability, as under the influence of a drug: to be freaked out on LSD.
    2. to lose or cause to lose emotional control from extreme excitement, shock, fear, joy, despair, etc.: Seeing the dead body freaked him out.

Origin of freak

1
1555–65; 1965–70 for def 6; perhaps akin to Old English frīcian to dance
Can be confusedfreak phreak

Synonyms for freak

See more synonyms for on Thesaurus.com
3. vagary, quirk, crotchet.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for freak out

freak out

verb (adverb)
  1. informal to be or cause to be in a heightened emotional state, such as that of fear, anger, or excitement

freak

1
noun
  1. a person, animal, or plant that is abnormal or deformed; monstrosity
    1. an object, event, etc, that is abnormal or extremely unusual
    2. (as modifier)a freak storm
  3. a personal whim or caprice
  4. informal a person who acts or dresses in a markedly unconventional or strange way
  5. informal a person who is obsessed with something specifieda jazz freak
verb
  1. See freak out

Word Origin for freak

C16: of obscure origin

freak

2
noun
  1. a fleck or streak of colour
verb
  1. (tr) to streak with colour; variegate

Word Origin for freak

C17: from earlier freaked, probably coined by Milton, based on streak 1 + obsolete freckt freckled; see freckle
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 freak out
n.

also freakout "bad psychedelic drug trip or something comparable to one," 1966 (despite an amusing coincidental appearance of the phrase dug up by the OED in "Fanny Hill" from 1749), from verbal phrase freak out, attested from 1965 in the drug sense (from 1902 in a sense "change, distort, come out of alignment"); see freak (n.). Freak (n.) "drug user" is attested from 1945.

She had had her freak out, and had pretty plentifully drowned her curiosity in a glut of pleasure .... [Cleland, "Memoirs of a Woman of Pleasure," 1749]

freak

n.

1560s, "sudden turn of mind," of unknown origin, perhaps related to Old English frician "to dance" (not recorded in Middle English, but the word may have survived in dialect) [OED, Barnhart], or perhaps from Middle English frek "bold, quickly," from Old English frec "greedy, gluttonous" (cf. German frech "bold, impudent").

Sense of "capricious notion" (1560s) and "unusual thing, fancy" (1784) preceded that of "strange or abnormal individual" (first in freak of nature, 1847; cf. Latin lusus naturæ, used in English from 1660s). The sense in health freak, ecology freak, etc. is attested from 1908 (originally Kodak freak, a camera buff). Freak show attested from 1887.

freak

v.

"change, distort," 1911, from freak (n.). Earlier, "to streak or fleck randomly" (1630s). Related: Freaked; freaking.

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with freak out

freak out

1

Experience or cause to experience hallucinations, paranoia, or other frightening feelings as a result of taking a mind-altering drug. For example, They were freaking out on LSD or some other drug. [Slang; mid-1960s]

2

Behave or cause to behave irrationally and uncontrollably, with enthusiasm, excitement, fear, or madness. For example, The band's wild playing made the audience freak out, or It was such a close accident, it really freaked me out, or She freaked out and ended up in the psychiatric ward. [Slang; 1960s] Also see flip one's lid; wig out.

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