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

decapitation \decap`ita"tion\, n. ll. decapitatio: cf. f.
   d'ecapitation.
   the act of beheading; beheading.
   1913 webster

[2] : WordNet (r) 2.0

decapitation
     n 1: execution by cutting off the victim's head syn: beheading
     2: killing by cutting off the head syn: beheading
see also:
beheading 

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

decapitation, punishment. the punishment of putting a person to death by 
taking off his head. 

Decapitation >> D Words
Decapitation, definition of term: Decapitation
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