What is "to borrow trouble"

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.

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.

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

   Rites borrowed from the ancients.
   --Macaulay.

   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.

4. To feign or counterfeit. ``Borrowed hair.''
   --Spenser.

   The borrowed majesty of England.
   --Shak.

5. To receive; to take; to derive.

   Any drop thou borrowedst from thy mother.
   --Shak.

   To borrow trouble, to be needlessly troubled; to be overapprehensive.