The Collaborative International Dictionary of English v.0.48:

Dairy \Dai"ry\ (d[=a]"r[y^]), n.; pl. Dairies (-r[i^]z). [OE.
   deierie, from deie, daie, maid; of Scand. origin; cf. Icel.
   deigja maid, dairymaid, Sw. deja, orig., a baking maid, fr.
   Icel. deig. [root]66. See Dough.]
   1. The place, room, or house where milk is kept, and
      converted into butter or cheese.
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            What stores my dairies and my folds contain.
                                                  --Dryden.
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   2. That department of farming which is concerned in the
      production of milk, and its conversion into butter and
      cheese.
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            Grounds were turned much in England either to
            feeding or dairy; and this advanced the trade of
            English butter.                       --Temple.
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   3. A dairy farm. [R.]
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   Note: Dairy is much used adjectively or in combination; as,
         dairy farm, dairy countries, dairy house or dairyhouse,
         dairyroom, dairywork, etc.
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