The Collaborative International Dictionary of English v.0.48:

Dial \Di"al\, n. [LL. dialis daily, fr. L. dies day. See
   Deity.]
   1. An instrument, formerly much used for showing the time of
      day from the shadow of a style or gnomon on a graduated
      arc or surface; esp., a sundial; but there are lunar and
      astral dials. The style or gnomon is usually parallel to
      the earth's axis, but the dial plate may be either
      horizontal or vertical.
      [1913 Webster]

   2. The graduated face of a timepiece, on which the time of
      day is shown by pointers or hands.
      [1913 Webster]

   3. A miner's compass.
      [1913 Webster]

   Dial bird (Zool.), an Indian bird (Copsychus saularius),
      allied to the European robin. The name is also given to
      other related species.

   Dial lock, a lock provided with one or more plates having
      numbers or letters upon them. These plates must be
      adjusted in a certain determined way before the lock can
      be operated.

   Dial plate, the plane or disk of a dial or timepiece on
      which lines and figures for indicating the time are
      placed.
      [1913 Webster]