barndoor

from WordNet (r) 3.0 (2006)

barndoor
    n 1: an opaque adjustable flap on a lamp fixture; used in
         photography to cut off light from particular areas

from The Collaborative International Dictionary of English v.0.48

barndoor \barndoor\ n.
   An opaque adjustable flap on a lamp fixture; used in
   photography to cut off light from particular areas.
   [WordNet 1.5]

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