The Collaborative International Dictionary of English v.0.48:

Buttery \But"ter*y\, n.; pl. Butteries. [OE. botery, botry;
   cf. LL. botaria wine vessel; also OE. botelerie, fr. F.
   bouteillerie, fr. boutellie bottle. Not derived from butter.
   See Bottle a hollow vessel, Butt a cask.]
   1. An apartment in a house where butter, milk and other
      provisions are kept.
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            All that need a cool and fresh temper, as cellars,
            pantries, and butteries, to the north. --Sir H.
                                                  Wotton.
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   2. A room in some English colleges where liquors, fruit, and
      refreshments are kept for sale to the students.
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            And the major Oxford kept the buttery bar. --E.
                                                  Hall.
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   3. A cellar in which butts of wine are kept. --Weale.
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   Buttery hatch, a half door between the buttery or kitchen
      and the hall, in old mansions, over which provisions were
      passed. --Wright.
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