The Collaborative International Dictionary of English v.0.48:

Immure \Im*mure"\, v. t. [imp. & p. p. Immured; p. pr. & vb.
   n. Immuring.] [Pref. im- in + mure: cf. F. emmurer.]
   1. To wall around; to surround with walls. [Obs.] --Sandys.
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   2. To inclose whithin walls, or as within walls; hence, to
      shut up; to imprison; to incarcerate.
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            Those tender babes
            Whom envy hath immured within your walls. --Shak.
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            This huge convex of fire,
            Outrageous to devour, immures us round. --Milton.
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