N-COUNT 黑马(最近刚取得或将要取得成功的新人) If you describe someone as a dark horse, you mean that people know very little about them, although they may have recently had success or may be about to have success. 黑马(最近刚取得或将要取得成功的新人)
Until recently A. S. Byatt was a dark horse, known only by those steeped in literature.