The Collaborative International Dictionary of English v.0.48:

Mortgage \Mort"gage\, v. t. [imp. & p. p. Mortgaged; p. pr. &
   vb. n. Mortgaging.]
   1. (Law) To grant or convey, as property, for the security of
      a debt, or other engagement, upon a condition that if the
      debt or engagement shall be discharged according to the
      contract, the conveyance shall be void, otherwise to
      become absolute, subject, however, to the right of
      redemption.
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   2. Hence: To pledge, either literally or figuratively; to
      make subject to a claim or obligation.
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            Mortgaging their lives to covetise.   --Spenser.
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            I myself an mortgaged to thy will.    --Shak.
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