The Collaborative International Dictionary of English v.0.48:

Milky \Milk"y\, a.
   1. Consisting of, or containing, milk.
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            Pails high foaming with a milky flood. --Pope.
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   2. Like, or somewhat like, milk; whitish and turbid; as, the
      water is milky. "Milky juice." --Arbuthnot.
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   3. Yielding milk. "Milky mothers." --Roscommon.
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   4. Mild; tame; spiritless.
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            Has friendship such a faint and milky heart? --Shak.
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   Milky Way. (Astron.) See Galaxy, 1.
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WordNet (r) 3.0 (2006):

milky
    adj 1: resembling milk in color not clear; "milky glass" [syn:
           milky, milklike, whitish]

Moby Thesaurus II by Grady Ward, 1.0:

48 Moby Thesaurus words for "milky":
   argent, argentine, bland, canescent, chalky, changeable,
   cretaceous, fleecy-white, frosted, frosty, grizzled, grizzly,
   halfhearted, hoar, hoary, indecisive, infirm of purpose,
   infirm of will, insipid, irresolute, lacteal, lacteous, lactescent,
   lactic, lactiferous, lily-white, marble, marmoreal, milch, milk,
   milk-and-water, mushy, neutral, niveous, platinum, pure white,
   silver, silvered, silvery, snow-white, snowy, swan-white,
   tasteless, vapid, watery, white, white as snow, wishy-washy