The Collaborative International Dictionary of English v.0.48:

Stab \Stab\ (st[a^]b), v. t. [imp. & p. p. Stabbed (st[a^]bd);
   p. pr. & vb. n. Stabbing.] [Cf. OD. staven to fix, fasten,
   fr. stave, staff, a staff, rod; akin to G. stab a staff,
   stick, E. staff; also Gael. stob to stab, as n., a stake, a
   stub. Cf. Staff.]
   1. To pierce with a pointed weapon; to wound or kill by the
      thrust of a pointed instrument; as, to stab a man with a
      dagger; also, to thrust; as, to stab a dagger into a
      person.
      [1913 Webster]

   2. Fig.: To injure secretly or by malicious falsehood or
      slander; as, to stab a person's reputation.
      [1913 Webster]