reaction

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Since the later part of the 20th century reaction has been used to mean little more than 'first impression' or 'initial response':

'I became more and more infatuated with that image as I grew older,' Rowan said and looked at me for some kind of reaction—fiction website, American English 2005 [Old English (up to 1150)C].

To do the word justice, it should involve some element of reacting to something that affects the person having (or asked to have) the reaction, rather than simply to passive hearing or reading of information. But the weakened meaning is well established, especially in the world of radio and television interviews: What is your reaction to the extension of VAT to domestic fuel?

Previous:	re-, re, raze
Next:	real, reality, reason

drop in securities prices after a sustained period of ad vancing prices, perhaps as the result of profit taking or adverse developments.
See also correction.

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Next:	Reading The Tape, Reaganomics

noun

1. An action elicited by a stimulus: response, retroaction. See action/inaction.
2. The way in which a machine or other thing performs or functions: behavior, functioning, operation, performance, working (often used in plural). See action/inaction, machine.

n

Definition: response
Antonyms: cause, question

The typical downward movement in the price of a security after the price had previously risen.

Investopedia Says:
The opposite of a recovery, a reaction is similar to a market correction but lacks the same intensity.

IN BRIEF: A happening in response to some other happening or force.

What life means to us is determined not so much by what life brings to us as by the attitude we bring to life; not so much by what happens to us as by our reaction to what happens. — Lewis L. Dunnington

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(in chemistry) any process in which molecules interact with one another, leading to chemical or physical change.

Previous:	reactant, reactancy of enzymes, re-entrant loop
Next:	reaction intermediate, reaction rate, reaction time

1. opposite action or counteraction; the response of a part to stimulation.
2. the phenomena caused by the action of chemical agents; a chemical process in which one substance is transformed into another substance or substances.

• chain r. — one which is self-propagating; a chemical process in which each time a free radical is destroyed a new one is formed.
• coupled r. — one in which the free energy released by one chemical reaction drives the other reaction.
• dark r. — photosynthetic reaction which fixes CO₂ into sugar and which occurs without exposure to light. Called also Calvin cycle.
• r. of degeneration — the reaction to electrical stimulation of muscles whose nerves have degenerated, consisting of loss of response to a faradic stimulation in a muscle, and to galvanic and faradic stimulation in the nerve.
• delayed r. — a reaction, such as an allergic reaction, occurring hours to days after exposure to an inducer.
• false negative r. — an erroneously negative reaction to a test.
• false positive r. — an erroneously positive reaction to a test.
• first set r. — see rejection.
• immune r. — 1. immune response; see also immunity.
— 2. formation of a papule and areola without development of a vesicle following smallpox vaccination.
• lengthening r. — reflex elongation of extensor muscles that permits flexion of a limb.
• leukemic r., leukemoid r. — a peripheral blood picture resembling leukemia or indistinguishable from it on the basis of morphological appearance alone, characterized by immature leukocytes in the blood.
• r. pattern analysis — designed to replace archaic, non-specific descriptions of the reactions of the skin to noxious influences; recommended categories are (1) perivascular dermatitis, (2) interface dermatitis, (3) vasculitis, (4) nodular and diffuse dermatitis, (5) intradermal vesicular and pustular dermatitis, (6) subepidermal vesicular and pustular dermatitis, (7) perifolliculitis, folliculitis and furunculosis, (8) fibrosing dermatitis, (9) panniculitis, (10) atrophic dermatosis, (11) mixed reaction patterns.
• second set r. — see rejection.
• r. specificity — lack of production of by-products in enzymatic reactions with yields of products being nearly 100%.
• Strauss r. — development of suppurative peritonitis, localized to the scrotal sac, in the guinea pig after the intraperitoneal injection of material containing Burkholderia mallei.
• stress r. — 1. alarm reaction.
— 2. gross stress reaction.
• r. time — the time elapsing between the application of a stimulus and the resulting reaction.
• wheal–flare r. — a cutaneous sensitivity rection to skin injury or administration of antigen, due to histamine production and marked by edematous elevation and erythematous flare.

(rē-ak′shən)
n

Opposite action, or counteraction; the response of a part to stimulation; a chemical process in which one substance is transformed into another substance or substances.

For a list of words related to reaction, see:

• Philosophies, Principles, and Parties - reaction: resistance to change and clinging to old or outmoded social and political forms

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Dansk (Danish)
n. - reaktion, effekt

idioms:

• reaction against    modvilje imod

Nederlands (Dutch)
reactie, reactionaire neiging

Français (French)
n. - réaction, (Méd) réaction, (Chim) réaction, (Pol) réaction

idioms:

• reaction against    réaction contre

Deutsch (German)
n. - Reaktion, Gegenreaktion

idioms:

• reaction against    Gegenreaktion

Ελληνική (Greek)
n. - αντίδραση

idioms:

• reaction against    αντιδράσεις εναντίον

Italiano (Italian)
reazione

idioms:

• reaction against    reazione contro

Português (Portuguese)
n. - reação (f), contra-ataque (m)

idioms:

• reaction against    reagir contra

Русский (Russian)
реакция

idioms:

• reaction against    ответная реакция

Español (Spanish)
n. - reacción

idioms:

• reaction against    reacción contra, reacción negativa

Svenska (Swedish)
n. - reaktion

中文（简体）(Chinese (Simplified))
反应, 反动, 反作用

idioms:

• reaction against    对...的反应

中文（繁體）(Chinese (Traditional))
n. - 反應, 反動, 反作用

idioms:

• reaction against    對...的反應

한국어 (Korean)
n. - 반작용하다, 반응, 반동

日本語 (Japanese)
n. - 反動, 反作用, 反応, 反発, 反動力, 核反応, 逆行

idioms:

• reaction against    対する反応

العربيه (Arabic)
‏(الاسم) رد فعل‏

עברית (Hebrew)
n. - ‮תגובה, ריאקציה, שינוי גמור, נסיגה, התנגדות לקידמה, נסגנות, רושם מיידי/ראשוני‬

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