The Collaborative International Dictionary of English v.0.48:

Intrench \In*trench"\, v. t. [imp. & p. p. Intrenched; p. pr.
   & vb. n. Intrenching.]
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   1. To cut in; to furrow; to make trenches in or upon.
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            It was this very sword intrenched it. --Shak.
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            His face
            Deep scars of thunder had intrenched. --Milton.
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   2. To surround with a trench or with intrenchments, as in
      fortification; to fortify with a ditch and parapet; as,
      the army intrenched their camp, or intrenched itself. "In
      the suburbs close intrenched." --Shak.
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