The Collaborative International Dictionary of English v.0.48:

Douse \Douse\, v. i.
   To fall suddenly into water. --Hudibras.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Douse \Douse\, v. t. [AS. dw[ae]scan. (Skeat.)]
   To put out; to extinguish; as, douse the lights. [Slang] " To
   douse the glim." --Sir W. Scott.
   [1913 Webster]

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]

WordNet (r) 3.0 (2006):

douse
    v 1: put out, as of a candle or a light; "Douse the lights"
         [syn: douse, put out]
    2: wet thoroughly [syn: douse, dowse]
    3: dip into a liquid; "He dipped into the pool" [syn: dip,
       douse, duck]
    4: immerse briefly into a liquid so as to wet, coat, or
       saturate; "dip the garment into the cleaning solution"; "dip
       the brush into the paint" [syn: dunk, dip, souse,
       plunge, douse]
    5: lower quickly; "douse a sail"
    6: slacken; "douse a rope" [syn: douse, dowse]
    7: cover with liquid; pour liquid onto; "souse water on his hot
       face" [syn: drench, douse, dowse, soak, sop,
       souse]

Moby Thesaurus II by Grady Ward, 1.0:

65 Moby Thesaurus words for "douse":
   bang, baptize, bash, bat, belt, blow out, bop, bury, cast off,
   choke, crack, damp, deluge, dip, doff, drench, drop, drown, duck,
   dunk, engulf, extinguish, immerge, immerse, inundate, merge, out,
   overwhelm, plash, plunge in water, put off, put out, quench,
   remove, sink, slack, slam, slip out of, slop, slosh, smack, smash,
   smother, snuff, snuff out, soak, sop, souse, spatter, splatter,
   splosh, splurge, spurtle, stamp out, step out of, stifle, submerge,
   submerse, swash, take off, throw off, undo, unwrap, wet, whelm