The Collaborative International Dictionary of English v.0.48:

Delation \De*la"tion\, n. [L. delatio accusation: cf. F.
   d['e]lation.]
   1. Conveyance. [Obs. or Archaic]
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            In delation of sounds, the inclosure of them
            preserveth them.                      --Bacon.
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   2. (Law) Accusation by an informer. --Milman.
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