Sentence:  "Wild Risk...had his greatest successes as a steeplechaser rather than a flat racer... It is rare indeed that a <WSD>'chaser</WSD> - even one as good as wild risk - makes a good flat sire." 
Meaning of the word marked with <WSD> tags:  A horse:  a horse used for hunting;  a horse trained for steeplechasing, a steeplechaser. (from 14th c.)