The Collaborative International Dictionary of English v.0.48:

Slabber \Slab"ber\, v. i. [imp. & p. p. Slabbered; p. pr. &
   vb. n. Slabbering.] [OE. slaberen; akin to LG. & D.
   slabbern, G. schlabbern, LG. & D. slabben, G. schlabben,
   Icel. slafra. Cf. Slaver, Slobber, Slubber.]
   To let saliva or some liquid fall from the mouth carelessly,
   like a child or an idiot; to drivel; to drool. [Written also
   slaver, and slobber.]
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The Collaborative International Dictionary of English v.0.48:

Slobber \Slob"ber\, v. t. & i.
   See Slabber.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Slobber \Slob"ber\, n.
   1. See Slabber.
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   2. (Zool.) A jellyfish. [Prov. Eng.]
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   3. pl. (Vet.) Salivation.
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WordNet (r) 3.0 (2006):

slobber
    n 1: saliva spilling from the mouth [syn: drool, dribble,
         drivel, slobber]
    v 1: let saliva drivel from the mouth; "The baby drooled" [syn:
         drivel, drool, slabber, slaver, slobber,
         dribble]

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "slobber":
   asperge, babble, be insane, be stupid, bedew, bespatter,
   besprinkle, blather, blither, burble, dabble, damp, dampen, dash,
   dew, dither, dote, douche, dribble, drivel, drool, expectorate,
   expectoration, flattering tongue, foam, froth, gush, have a demon,
   hawk, hose, hose down, humect, humectate, humidify, insincerity,
   irrigate, maunder, moisten, mouth-watering, oiliness, paddle,
   ptyalism, rage, ramble, rant, rave, run amok, run mad, saliva,
   salivate, salivation, sialagogue, slabber, slaver, slop, slosh,
   smarm, sparge, spatter, spew, spit, spittle, splash, splatter,
   sponge, spray, sprinkle, sputum, swash, syringe,
   that flattering unction, unction, unctuousness, wander, water, wet,
   wet down