di·rec·tion·al /-ʃnəl, ʃənḷ/
 (a.)方向的


 directional
 方向 定向 向


 directional
      adj 1: relating to or indicating directions in space; "a
             directional microphone" [ant: omnidirectional]
      2: relating to direction toward a (nonspatial) goal; "he tried
         to explain the directional trends of modern science"
      3: showing the way by conducting or leading; imposing direction
         on; "felt his mother's directing arm around him"; "the
         directional role of science on industrial progress" [syn:
         directing, directive, guiding]