The Collaborative International Dictionary of English v.0.48:

Slat \Slat\, v. t. [imp. & p. p. Slatted; p. pr. & vb. n.
   Slatting.] [OE. slatten; cf. Icel. sletta to slap, to dab.]
   1. To slap; to strike; to beat; to throw down violently.
      [Prov. Eng. & Colloq. U.S.]
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            How did you kill him?
            Slat[t]ed his brains out.             --Marston.
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   2. To split; to crack. [Prov. Eng.] --Halliwell.
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   3. To set on; to incite. See 3d Slate. [Prov. Eng.]
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