The Collaborative International Dictionary of English v.0.48:

Borrow \Bor"row\, n.
   1. Something deposited as security; a pledge; a surety; a
      hostage. [Obs.]
      [1913 Webster]

            Ye may retain as borrows my two priests. --Sir W.
                                                  Scott.
      [1913 Webster]

   2. The act of borrowing. [Obs.]
      [1913 Webster]

            Of your royal presence I'll adventure
            The borrow of a week.                 --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Borrow \Bor"row\, v. t. [imp. & p. p. Borrowed; p. pr. & vb.
   n. Borrowing.] [OE. borwen, AS. borgian, fr. borg, borh,
   pledge; akin to D. borg, G. borg; prob. fr. root of AS.
   beorgan to protect. ?95. See 1st Borough.]
   1. To receive from another as a loan, with the implied or
      expressed intention of returning the identical article or
      its equivalent in kind; -- the opposite of lend.
      [1913 Webster]

   2. (Arith.) To take (one or more) from the next higher
      denomination in order to add it to the next lower; -- a
      term of subtraction when the figure of the subtrahend is
      larger than the corresponding one of the minuend.
      [1913 Webster]

   3. To copy or imitate; to adopt; as, to borrow the style,
      manner, or opinions of another.
      [1913 Webster]

            Rites borrowed from the ancients.     --Macaulay.
      [1913 Webster]

            It is not hard for any man, who hath a Bible in his
            hands, to borrow good words and holy sayings in
            abundance; but to make them his own is a work of
            grace only from above.                --Milton.
      [1913 Webster]

   4. To feign or counterfeit. "Borrowed hair." --Spenser.
      [1913 Webster]

            The borrowed majesty of England.      --Shak.
      [1913 Webster]

   5. To receive; to take; to derive.
      [1913 Webster]

            Any drop thou borrowedst from thy mother. --Shak.
      [1913 Webster]

   To borrow trouble, to be needlessly troubled; to be
      overapprehensive.
      [1913 Webster]

WordNet (r) 3.0 (2006):

borrow
    v 1: get temporarily; "May I borrow your lawn mower?" [ant:
         lend, loan]
    2: take up and practice as one's own [syn: adopt, borrow,
       take over, take up]