The Collaborative International Dictionary of English v.0.48:

Closet \Clos"et\, v. t. [imp. & p. p.Closeted p. pr. & vb. n.
   Closeting.]
   1. To shut up in, or as in, a closet; to conceal. [R.]
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            Bedlam's closeted and handcuffed charge. --Cowper.
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   2. To make into a closet for a secret interview.
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            He was to call a new legislature, to closet its
            members.                              --Bancroft.
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            He had been closeted with De Quadra.  --Froude.
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