WordNet (r) 3.0 (2006):

steeplechase
    n 1: a footrace of usually 3000 meters over a closed track with
         hurdles and a water jump
    2: a horse race over an obstructed course

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "steeplechase":
   Derby, Highland fling, Kentucky Derby, Preakness Stakes, and jump,
   bounce, bouncing, bound, bounding, broad jump, buck, buckjump,
   capering, capriole, chase, curvet, demivolt, flat race,
   flying jump, galliard, gelandesprung, grand jete, handicap,
   handicap race, handspring, harness race, high jump, hippety-hop,
   hop, hopping, horse race, hurdle, hurdle race, hurdling, jete, jig,
   jump, jump shot, jump turn, jump-hop, jump-off, jumping, lavolta,
   leap, leapfrog, leaping, long jump, morris, plate race, pole vault,
   pole vaulting, pounce, prancing, purse race, quarter-horse race,
   running broad jump, running high jump, saltation, saut de basque,
   ski jump, skip, skipping, spring, springing, stake, stake race,
   sweep, sweepstake, sweepstakes, the hurdles, timber topping,
   tour jete, trotting race, upleap, upspring, vault, vaulting