The Collaborative International Dictionary of English v.0.48:

Fulsome \Ful"some\, a. [Full, a. + -some.]
   1. Full; abundant; plenteous; not shriveled. [Obs.]
      [1913 Webster]

            His lean, pale, hoar, and withered corpse grew
            fulsome, fair, and fresh.             --Golding.
      [1913 Webster]

   2. Offending or disgusting by overfullness, excess, or
      grossness; cloying; gross; nauseous; esp., offensive from
      excess of praise; as, fulsome flattery.
      [1913 Webster]

            And lest the fulsome artifice should fail
            Themselves will hide its coarseness with a veil.
                                                  --Cowper.
      [1913 Webster]

   3. Lustful; wanton; obscene; also, tending to obscenity.
      [Obs.] "Fulsome ewes." --Shak. -- Ful"some*ly, adv. --
      Ful"some*ness, n. --Dryden.
      [1913 Webster]

WordNet (r) 3.0 (2006):

fulsome
    adj 1: unpleasantly and excessively suave or ingratiating in
           manner or speech; "buttery praise"; "gave him a fulsome
           introduction"; "an oily sycophantic press agent";
           "oleaginous hypocrisy"; "smarmy self-importance"; "the
           unctuous Uriah Heep"; "soapy compliments" [syn:
           buttery, fulsome, oily, oleaginous, smarmy,
           soapy, unctuous]

Moby Thesaurus II by Grady Ward, 1.0:

299 Moby Thesaurus words for "fulsome":
   Fescennine, Gongoresque, Johnsonian, Rabelaisian, abhorrent,
   abject, abominable, adulatory, affected, arrant, atrocious, awful,
   bad, bad-smelling, barfy, base, bawdy, beastly, bedizened,
   beggarly, below contempt, beneath contempt, big-sounding,
   blameworthy, bland, blandishing, blarneying, blue, bombastic,
   brackish, brutal, buttery, cajoling, canting, cheesy, cloying,
   complimentary, contemptible, convoluted, courtierly, courtly,
   crude, crummy, debased, declamatory, degraded, deplorable,
   depraved, despicable, detestable, dire, dirty, disarming,
   disgusting, dreadful, egregious, elevated, enormous, euphuistic,
   excessive, execrable, extravagant, exuberant, fair-spoken, fawning,
   fecal, fetid, filthy, fine-spoken, flagrant, flamboyant, flaming,
   flashy, flattering, flaunting, forbidding, foul, foul-mouthed,
   foul-spoken, foul-tongued, frowsty, frowy, frowzy, funky, fusty,
   gamy, garish, gaudy, glib, grandiloquent, grandiose, grandisonant,
   grave, graveolent, grievous, gross, gushing, hateful, heinous,
   hero-worshiping, high, high-flowing, high-flown, high-flying,
   high-sounding, highfalutin, holier-than-thou, honey-mouthed,
   honey-tongued, honeyed, horrible, horrid, hypocritical, icky,
   idolatrous, ignoble, ill-smelling, impure, infamous, ingratiating,
   inkhorn, insincere, insinuating, ithyphallic, labyrinthine,
   lamentable, lavish, lewd, lexiphanic, lionizing, little, loathsome,
   lofty, lousy, low, low-down, lumpen, lurid, maggoty, magniloquent,
   malodorous, mangy, mawkish, mealy-mouthed, mealymouthed, mean,
   measly, mephitic, meretricious, miasmal, miasmic, mildewed,
   mildewy, miserable, moldy, monstrous, musty, nasty, nauseant,
   nauseating, nauseous, nefarious, nidorous, noisome, notorious,
   noxious, objectionable, obnoxious, obscene, obsequious, odious,
   odorous, offensive, oily, oily-tongued, oleaginous, olid, orotund,
   ostentatious, outrageous, overappreciative, overdone,
   overelaborate, overinvolved, overpraising, overripe, overwrought,
   paltry, pecksniffian, pedantic, petty, pharisaical, pitiable,
   pitiful, poisonous, poky, pompous, poor, pornographic, pretentious,
   profuse, putrid, rancid, rank, raunchy, reasty, reasy, rebarbative,
   reechy, reeking, reeky, regrettable, repellent, reprehensible,
   reptilian, repugnant, repulsive, revolting, rhetorical, ribald,
   rotten, sad, salacious, sanctimonious, satiating, sating, scabby,
   scandalous, schlock, scrubby, scruffy, scummy, scurrile,
   scurrilous, scurvy, sensational, sensationalistic, sententious,
   shabby, shameful, shocking, shoddy, showy, sickening, slick, slimy,
   slobbery, small, smarmy, smellful, smelling, smelly, smoking-room,
   smooth, smooth-spoken, smooth-tongued, smug, smutty, soapy,
   soft-soaping, soft-spoken, sonorous, sordid, spoiled, squalid,
   stenchy, stilted, stinking, strong, stuffy, suave, suave-spoken,
   sulfurous, sultry, sycophantic, tall, terrible, too bad, tortuous,
   uncensorious, unchaste, unclean, uncritical, uncriticizing,
   unctuous, unmentionable, unprintable, unrepeatable, unreproachful,
   vile, villainous, vomity, weevily, wheedling, woeful, worst,
   worthless, wretched, yucky