VERB (3)

1. incite to commit a crime or an evil deed;
- Example: "He suborned his butler to cover up the murder of his wife"

2. procure (false testimony or perjury);

3. induce to commit perjury or give false testimony;
- Example: "The President tried to suborn false witnesses"

The Collaborative International Dictionary of English v.0.48:

Suborn \Sub*orn"\, v. t. [imp. & p. p. Suborned; p. pr. & vb.
   n. Suborning.] [F. suborner, L. subornare; sub under,
   secretly + ornare to furnish, provide, equip, adorn. See
   Ornament.]
   1. (Law) To procure or cause to take a false oath amounting
      to perjury, such oath being actually taken. --Sir W. O.
      Russell.
      [1913 Webster]

   2. To procure privately, or by collusion; to procure by
      indirect means; to incite secretly; to instigate.
      [1913 Webster]

            Thou art suborned against his honor.  --Shak.
      [1913 Webster]

            Those who by despair suborn their death. --Dryden.
      [1913 Webster]

WordNet (r) 3.0 (2006):

suborn
    v 1: incite to commit a crime or an evil deed; "He suborned his
         butler to cover up the murder of his wife"
    2: procure (false testimony or perjury)
    3: induce to commit perjury or give false testimony; "The
       President tried to suborn false witnesses"