parenticide

from The Collaborative International Dictionary of English v.0.48

Parenticide \Pa*ren"ti*cide\, n. [L. parenticida a parricide;
   parens parent + caedere to kill.]
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   1. The act of one who kills one's own parent. [R.]
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   2. One who kills one's own parent; a parricide. [R.]
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