reaction


reaction
reaction [rē ak′shən]
n.
1. a return or opposing action, force, influence, etc.
2. a response, as to a stimulus or influence
3. a movement back to a former or less advanced condition, stage, etc.; esp., such a movement or tendency in economics or politics; extreme conservatism
4. Chem.
a) the mutual action of substances undergoing chemical change
b) a process that involves changes within the nucleus of an atom
c) the state resulting from such changes
5. Med.
a) an action induced by resistance to another action
b) the effect produced by an allergen
c) a depression or exhaustion of energy following nervous tension, overstimulation, etc.
d) an increased activity following depression
6. Physiol. Psychol. an organic response to a stimulus
reactional
adj.

English World dictionary. . 2014.

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  • réaction — [ reaksjɔ̃ ] n. f. • 1690; de re et action I ♦ Sc. 1 ♦ Mécan. Force qu un corps agissant sur un autre détermine en retour chez celui ci. Principe de l égalité de l action et de la réaction (énoncé par Newton) :un corps qui exerce sur un autre une …   Encyclopédie Universelle

  • Reaction — Réaction Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom …   Wikipédia en Français

  • Reaction — Re*ac tion (r[ e]*[a^]k sh[u^]n), n. [Cf. F. r[ e]action.] 1. Any action in resisting other action or force; counter tendency; movement in a contrary direction; reverse action. [1913 Webster] 2. (Chem.) The mutual or reciprocal action of chemical …   The Collaborative International Dictionary of English

  • Réaction! — Réaction ! Réaction ! Saison 1 Épisode n°16 Titre original The Peanut Reaction Code de production 116 1e diffusion aux É. U. 12 mai 2008 …   Wikipédia en Français

  • Réaction ! — Réaction ! Saison 1 Épisode n°16 Titre original The Peanut Reaction Code de production 116 1e diffusion aux É. U. 12 mai 2008 …   Wikipédia en Français

  • reaction — Since the later part of the 20c 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 …   Modern English usage

  • reaction — (n.) 1610s, from RE (Cf. re ) again, anew + ACTION (Cf. action) (q.v.). Modeled on Fr. réaction, older It. reattione, from M.L. reactionem (nom. reactio), from L.L. react , pp. stem of reagere react, from re …   Etymology dictionary

  • reaction — I (opposition) noun backfire, backlash, challenge, clash, conflict, contradiction, contrariety, countertendency, differences, disagreement, disapprobation, discountenance, expression of disapproval, objection, offset, polarity, protest, rebound,… …   Law dictionary

  • reaction — [n1] response acknowledgment, answer, attitude, backfire, backlash, back talk*, boomerang*, comeback, compensation, counteraction, counterbalance, counterpoise, double take*, echo, feedback, feeling, hit, kick, kickback, knee jerk*, lip*, opinion …   New thesaurus

  • Reaction — (v. lat.), 1) so v.w. Gegenbewegung, Gegendruck, Gegenwirkung, d.h. eine rückwirkende Thätigkeit, welche überall stattfindet, wo entgegengesetzte Kräfte einander entgegen wirken u. sich ins Gleichgewicht zu setzen suchen. 2) Die Erscheinung, daß… …   Pierer's Universal-Lexikon

  • Reaction — Reaction, Gegenwirkung, Gegenbewegung …   Damen Conversations Lexikon