The Collaborative International Dictionary of English v.0.48:

Swash \Swash\, v. i. [imp. & p. p. Swashed; p. pr. & vb. n.
   Swashing.] [Probably of imitative origin; cf. Sw. svasska
   to splash, and, for sense 3, Sw. svassa to bully, to
   rodomontade.]
   1. To dash or flow noisily, as water; to splash; as, water
      swashing on a shallow place.
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   2. To fall violently or noisily. [Obs.] --Holinshed.
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   3. To bluster; to make a great noise; to vapor or brag.
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