setback

disappointment

Synonyms: about-face, backset, bath, blow, bottom, check, comedown, defeat, delay, difficulty, drawing board, flip-flop, hindrance, hitch, hold-up, impediment, misfortune, obstacle, rebuff, regress, regression, reversal, reversal of fortune, reverse, slowdown, stumbling block, trouble, upset, whole new ballgame

Antonyms: achievement, advance, blessing, boon, boost, success