#oak  the hard durable wood of any oak; used especially for furniture and flooring
  supertype:  wood  the hard fibrous lignified substance under the bark of trees
  substance of:  oak_tree
  subtype:  fumed_oak__fumedoak  oak given a weathered appearance by exposure to fumes of ammonia; used for cabinetwork
  subtype:  holm_oak  hard wood of the holm oak tree

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