A case or pair of boards covered with cloth or fancy paper, for binding a volume, or the periodical numbers or parts of a work; also a case for holding unbound serials, music, etc.

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1885.  C. Mackeson, Brit. Alm. Comp., 94. In some parts of the country identical titles are very differently applied. Among the double meanings … [is] Book Case Maker for a Cabinet-maker or Bookbinder.

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