[1] : The Collaborative International Dictionary of English v.0.48

instigation \in`stiga"tion\, n. l. instigatio: cf. f.
   instigation.
   the act of instigating, or the state of being instigated;
   incitement; esp. to evil or wickedness.
   1913 webster

         the baseness and villainy that . . . the instigation of
         the devil could bring the sons of men to. --south.
   1913 webster

[2] : WordNet (r) 2.0

instigation
     n 1: the verbal act of urging on syn: abetment
     2: deliberate and intentional triggering of trouble or
        discord syn: fomentation
see also:
abetment fomentation 

[3] : Moby Thesaurus II by Grady Ward, 1.0

24 moby thesaurus words for "instigation":
   agitation, arousal, catalyst, exasperation, excitation, excitement,
   firing, fomentation, goad, impetus, impulse, incentive, incitation,
   incitement, inflammation, irritation, pep rally, pep talk,
   provocation, rabble-rousing, spur, stimulation, stirring,
   stirring-up

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

instigation. the act by which one incites another to do something, as to 
injure a third person, or to commit some crime or misdemeanor, to commence 
a suit or to prosecute a criminal. vide accomplice. 

Instigation >> I Words
Instigation, definition of term: Instigation
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