The Collaborative International Dictionary of English v.0.48:

Chaparral \Cha`par*ral"\, n. [Sp., fr. chaparro an evergeen
   oak.]
   1. A thicket of low evergreen oaks.
      [1913 Webster]

   2. An almost impenetrable thicket or succession of thickets
      of thorny shrubs and brambles.
      [1913 Webster]

   Chaparral cock; fem. Chaparral hen (Zool.), a bird of the
      cuckoo family (Geococcyx Californianus), noted for
      running with great speed. It ranges from California to
      Mexico and eastward to Texas; -- called also road
      runner, ground cuckoo, churea, and snake killer. It
      is the state bird of New Mexico.
      [1913 Webster +PJC] chapati

WordNet (r) 3.0 (2006):

Geococcyx californianus
    n 1: speedy largely terrestrial bird found from California and
         Mexico to Texas [syn: roadrunner, chaparral cock,
         Geococcyx californianus]