﹝Former practice of disguising a fast horse with dark paint and entering it in a race with inferior horses to pull off a betting coup.﹞

﹝从前用黑漆涂良马，而将之和较劣等的马一同比赛，以赢取赌金的作为。﹞

Little known entrant in a race or contest not given much chance of winning.

黑马(竞赛之中不受注目且不被视为赢家的一员)。