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reactionmore about reaction


  4  definitions  found 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
  Reaction  \Re*ac"tion\,  n.  (Psycophysics) 
  A  regular  or  characteristic  response  to  a  stimulation  of  the 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
  Widal's  \Wi*dal's"\,  or  Widal  test  \Wi*dal",  test\  or  reaction 
  \reaction\  .  [After  Fernand  Widal  (b.  1862),  French  physician.] 
  A  test  for  typhoid  fever  based  on  the  fact  that  blood  serum 
  of  one  affected,  in  a  bouillon  culture  of  typhoid  bacilli, 
  causes  the  bacilli  to  agglutinate  and  lose  their  motility. 
  From  Webster's  Revised  Unabridged  Dictionary  (1913)  [web1913]: 
  Reaction  \Re*ac"tion\,  n.  [Cf.  F.  r['e]action.] 
  1.  Any  action  in  resisting  other  action  or  force;  counter 
  tendency;  movement  in  a  contrary  direction;  reverse 
  2.  (Chem.)  The  mutual  or  reciprocal  action  of  chemical  agents 
  upon  each  other  or  the  action  upon  such  chemical  agents 
  of  some  form  of  energy,  as  heat,  light,  or  electricity, 
  resulting  in  a  chemical  change  in  one  or  more  of  these 
  agents,  with  the  production  of  new  compounds  or  the 
  manifestation  of  distinctive  characters.  See  {Blowpipe 
  reaction},  {Flame  reaction},  under  {Blowpipe},  and 
  3.  (Med.)  An  action  included  by  vital  resistance  to  some 
  other  action  depression  or  exhaustion  of  vital  force 
  consequent  on  overexertion  or  overstimulation  heightened 
  activity  and  overaction  succeeding  depression  or  shock. 
  4.  (Mech.)  The  force  which  a  body  subjected  to  the  action  of 
  a  force  from  another  body  exerts  upon  the  latter  body  in 
  the  opposite  direction. 
  Reaction  is  always  equal  and  opposite  to  action 
  that  is  to  say  the  actions  of  two  bodies  upon  each 
  other  are  always  equal  and  in  opposite  directions. 
  --Sir  I. 
  Newton  (3d  Law 
  of  Motion). 
  5.  (Politics)  Backward  tendency  or  movement  after  revolution, 
  reform,  or  great  progress  in  any  direction. 
  The  new  king  had  at  the  very  moment  at  which  his 
  fame  and  fortune  reached  the  highest  point, 
  predicted  the  coming  reaction.  --Macaulay. 
  {Reaction  time}  (Physiol.),  in  nerve  physiology,  the  interval 
  between  the  application  of  a  stimulus  to  an  end  organ  of 
  sense  and  the  reaction  or  resulting  movement;  --  called 
  also  {physiological  time}. 
  {Reaction  wheel}  (Mech.),  a  water  wheel  driven  by  the 
  reaction  of  water,  usually  one  in  which  the  water, 
  entering  it  centrally,  escapes  at  its  periphery  in  a 
  direction  opposed  to  that  of  its  motion  by  orifices  at 
  right  angles,  or  inclined,  to  its  radii. 
  From  WordNet  r  1.6  [wn]: 
  n  1:  a  response  that  reveals  a  person's  feelings  or  attitude;  "he 
  was  pleased  by  the  audience's  reaction  to  his 
  performance";  "John  feared  his  mother's  reaction  when 
  she  saw  the  broken  lamp" 
  2:  a  bodily  process  occurring  due  to  the  effect  of  some 
  foregoing  stimulus  or  agent;  "a  bad  reaction  to  the 
  medicine";  "his  responses  have  slowed  with  age"  [syn:  {response}] 
  3:  an  idea  evoked  by  some  experience;  "his  reaction  to  the  news 
  was  to  start  planning  what  to  do" 
  4:  (chemistry)  a  process  in  which  one  or  more  substances  are 
  changed  into  others  "there  was  a  chemical  reaction  of  the 
  lime  with  the  ground  water"  [syn:  {chemical  reaction}] 
  5:  doing  something  in  opposition  to  another  way  of  doing  it 
  that  you  don't  like  "his  style  of  painting  was  a  reaction 
  against  cubism" 
  6:  extreme  conservatism  in  political  or  social  matters;  "the 
  forces  of  reaction  carried  the  election" 
  7:  (mechanics)  the  equal  and  opposite  force  that  is  produced 
  when  any  force  is  applied  to  a  body;  "every  action  has  an 
  equal  and  opposite  reaction" 

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