Acclaimed Russian dancer (8)
I believe the answer is:
nijinsky
(Other definitions for nijinsky that I've seen before include "Russian ballet dancer, d. 1950 - racehorse, winner of the English Triple Crown, 1970" , "Great dancer, great horse" , "Great Russian male dancer/ choreographer, died 1950." , "Great dancer, d. 1950 - great racehorse, d. 1992" , "Russ. dancer; racehorse" .)