to back up

Back \Back\ (b[a^]k), v. t. [imp. & p. p. {Backed} (b[a^]kt); p.
   pr. & vb. n. {Backing}.]
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   1. To get upon the back of; to mount.
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            I will back him [a horse] straight.   --Shak.
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   2. To place or seat upon the back. [R.]
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            Great Jupiter, upon his eagle backed,
            Appeared to me.                       --Shak.
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   3. To drive or force backward; to cause to retreat or recede;
      as, to back oxen.
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   4. To make a back for; to furnish with a back; as, to back
      books.
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   5. To adjoin behind; to be at the back of.
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            A garden . . . with a vineyard backed. --Shak.
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            The chalk cliffs which back the beach. --Huxley.
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   6. To write upon the back of; as, to back a letter; to
      indorse; as, to back a note or legal document.
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   7. To support; to maintain; to second or strengthen by aid or
      influence; as, to back a friend. "The Parliament would be
      backed by the people." --Macaulay.
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            Have still found it necessary to back and fortify
            their laws with rewards and punishments. --South.
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            The mate backed the captain manfully. --Blackw. Mag.
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   8. To bet on the success of; -- as, to back a race horse.
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   {To back an anchor} (Naut.), to lay down a small anchor ahead
      of a large one, the cable of the small one being fastened
      to the crown of the large one.

   {To back the field}, in horse racing, to bet against a
      particular horse or horses, that some one of all the other
      horses, collectively designated "the field", will win.

   {To back the oars}, to row backward with the oars.

   {To back a rope}, to put on a preventer.

   {To back the sails}, to arrange them so as to cause the ship
      to move astern.

   {To back up}, to support; to sustain; as, to back up one's
      friends.

   {To back a warrant} (Law), is for a justice of the peace, in
      the county where the warrant is to be executed, to sign or
      indorse a warrant, issued in another county, to apprehend
      an offender.

   {To back water} (Naut.), to reverse the action of the oars,
      paddles, or propeller, so as to force the boat or ship
      backward.
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