The Collaborative International Dictionary of English v.0.48:

Arrowheaded \Ar"row*head`ed\, a.
   Shaped like the head of an arrow; cuneiform.
   [1913 Webster]

   Arrowheaded characters, characters the elements of which
      consist of strokes resembling arrowheads, nailheads, or
      wedges; -- hence called also nail-headed, wedge-formed,
      cuneiform, or cuneatic characters; the oldest written
      characters used in the country about the Tigris and
      Euphrates, and subsequently in Persia, and abounding among
      the ruins of Persepolis, Nineveh, and Babylon. See
      Cuneiform.
      [1913 Webster]