accoding to dictionary.com:
hur·dle (noun)
1. a portable barrier over which contestants must leap in certain running races, usually a wooden frame with a hinged inner frame that swings down under impact to prevent injury to a runner who does not clear it.
2. hurdles, (used with a singular verb) a race in which contestants must leap over a number of such barriers placed at specific intervals around the track.
perhaps a wall in the center of the playing field that must be crossed to score?
