The DICT Development Group

  Barn \Barn\ (b[aum]rn), n. [OE. bern, AS. berern, bern; bere
     barley + ern, [ae]rn, a close place. [root]92. See Barley.]
     A covered building used chiefly for storing grain, hay, and
     other productions of a farm. In the United States a part of
     the barn is often used for stables.
     [1913 Webster]
  
     Barn owl (Zool.), an owl of Europe and America ({Aluco
        flammeus, or Strix flammea), which frequents barns and
        other buildings.
  
     Barn swallow (Zool.), the common American swallow ({Hirundo
        horreorum), which attaches its nest of mud to the beams
        and rafters of barns.
        [1913 Webster]

  barn owl
      n 1: mottled buff and white owl often inhabiting barns and other
           structures; important in rodent control [syn: barn owl,
           Tyto alba]