The Collaborative International Dictionary of English v.0.48:

Itch \Itch\ ([i^]ch), v. i. [imp. & p. p. Itched ([i^]cht); p.
   pr. & vb. n. Itching.] [OE. icchen, [yogh]icchen, AS.
   giccan; akin to D. jeuken, joken, G. jucken, OHG. jucchen.]
   [1913 Webster]
   1. To have an uneasy sensation in the skin, which inclines
      the person to scratch the part affected.
      [1913 Webster]

            My mouth hath itched all this long day. --Chaucer.
      [1913 Webster]

   2. To have a constant desire or teasing uneasiness; to long
      for; as, itching ears. "An itching palm." --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

itching
    n 1: an irritating cutaneous sensation that produces a desire to
         scratch [syn: itch, itchiness, itching]