The Collaborative International Dictionary of English v.0.48:

Douse \Douse\ (dous), v. t. [imp. & p. p. Doused (doust); p.
   pr. & vb. n. Dousing.] [Cf. Dowse, and OD. donsen to
   strike with the fist on the back, Sw. dunsa to fall down
   violently and noisily; perh. akin to E. din.]
   1. To plunge suddenly into water; to duck; to immerse; to
      dowse. --Bp. Stillingfleet.
      [1913 Webster]

   2. (Naut.) To strike or lower in haste; to slacken suddenly;
      as, douse the topsail.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "dousing":
   baptism, burial, burning out, controlling, damping, dip, dipping,
   duck, ducking, dunking, dying, engulfment, extinction,
   extinguishment, fire fighting, flame-out, going out, immergence,
   immersion, inundation, putting out, quenching, sinking,
   smotheration, smothering, snuffing, souse, sousing, stifling,
   submergence, submersion