The Collaborative International Dictionary of English v.0.48:

Watery \Wa"ter*y\, a. [AS. waeterig.]
   [1913 Webster]
   1. Of or pertaining to water; consisting of water. "The
      watery god." --Dryden. "Fish within their watery
      residence." --Milton.
      [1913 Webster]

   2. Abounding with water; wet; hence, tearful.
      [1913 Webster]

   3. Resembling water; thin or transparent, as a liquid; as,
      watery humors.
      [1913 Webster]

            The oily and watery parts of the aliment.
                                                  --Arbuthnot.
      [1913 Webster]

   4. Hence, abounding in thin, tasteless, or insipid fluid;
      tasteless; insipid; vapid; spiritless.
      [1913 Webster]

WordNet (r) 3.0 (2006):

watery
    adj 1: filled with water; "watery soil"
    2: wet with secreted or exuded moisture such as sweat or tears;
       "wiped his reeking neck" [syn: reeking, watery]
    3: relating to or resembling or consisting of water; "a watery
       substance"; "a watery color"
    4: overly diluted; thin and insipid; "washy coffee"; "watery
       milk"; "weak tea" [syn: watery, washy, weak]

Moby Thesaurus II by Grady Ward, 1.0:

171 Moby Thesaurus words for "watery":
   Lenten, Spartan, abstemious, airy, anemic, aquatic, aqueous,
   ascetic, attenuate, attenuated, austere, banal, bland, bloodless,
   boyish, changeable, dead, delicate, diaphanous, dilute, diluted,
   dwarfed, dwarfish, ethereal, excretory, exiguous, fade, fine,
   fine-drawn, finespun, flat, flavorless, flimsy, flowing, fluent,
   fluid, fluidal, fluidic, fluxible, fluxile, fluxional, fluxionary,
   frail, frugal, gauzy, girlish, gossamer, gracile, gruelly,
   halfhearted, hydrated, hydraulic, hydrous, impoverished, inane,
   indecisive, indifferent, infirm of purpose, infirm of will,
   insipid, insubstantial, irresolute, jejune, juicy, lachrymal,
   lachrymose, lacrimatory, lactational, lacteal, lacteous, lacy,
   lean, light, limited, liquid, liquidy, meager, mean, mild,
   milk-and-water, milky, miserly, misty, mushy, namby-pamby, narrow,
   neutral, niggardly, pallid, paltry, papery, pappy, parsimonious,
   plashy, poor, pulpy, puny, rare, rarefied, rheumy, runny, salivant,
   salivary, salivous, sapless, sappy, savorless, scant, scanty,
   scrawny, scrimp, scrimpy, secretional, secretive, secretory,
   seminal, serous, sialagogic, skimp, skimpy, slender, slenderish,
   slight, slight-made, slim, slimmish, slinky, sloppy, small, spare,
   sparing, spermatic, spiceless, splashy, stale, starvation, stingy,
   stinted, straitened, stunted, subsistence, subtle, succulent,
   svelte, swashy, sylphlike, tasteless, tenuous, thin, thin-bodied,
   thin-set, thin-spun, thinnish, threadlike, unflavored,
   unnourishing, unnutritious, unsavory, vague, vapid, washy,
   wasp-waisted, watered, watered-down, watering, waterish, weak,
   willowy, wiredrawn, wishy-washy, wispy