The Collaborative International Dictionary of English v.0.48:

Numb \Numb\ (n[u^]m), a. [OE. nume, nome, prop., seized, taken,
   p. p. of nimen to take, AS. niman, p. p. numen. [root]7. See
   Nimble, Nomad, and cf. Benumb.]
   [1913 Webster]
   1. Enfeebled in, or destitute of, the power of sensation and
      motion; rendered torpid; benumbed; insensible; as, the
      fingers or limbs are numb with cold. "A stony image, cold
      and numb." --Shak.
      [1913 Webster]

   2. Producing numbness; benumbing; as, the numb, cold night.
      [Obs.] --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Numb \Numb\, v. t. [imp. & p. p. Numbed (n[u^]md); p. pr. &
   vb. n. Numbing (n[u^]m"[i^]ng).]
   To make numb; to deprive of the power of sensation or motion;
   to render senseless or inert; to deaden; to benumb; to
   stupefy.
   [1913 Webster]

         For lazy winter numbs the laboring hand. --Dryden.
   [1913 Webster]

         Like dull narcotics, numbing pain.       --Tennyson.
   [1913 Webster]

WordNet (r) 3.0 (2006):

numb
    adj 1: lacking sensation; "my foot is asleep"; "numb with cold"
           [syn: asleep(p), benumbed, numb]
    2: (followed by `to') not showing human feeling or sensitivity;
       unresponsive; "passersby were dead to our plea for help";
       "numb to the cries for mercy" [syn: dead(p), numb(p)]
    3: so frightened as to be unable to move; stunned or paralyzed
       with terror; petrified; "too numb with fear to move"
    v 1: make numb or insensitive; "The shock numbed her senses"
         [syn: numb, benumb, blunt, dull]