flat–out

having no exceptions or restrictions regarded their son-in-law as a flat-out loser and let him know it Synonyms all-out, arrant, blank, blooming [chiefly British], bodacious [Southern & Midland], categorical (also categoric), clean, complete, consummate, cotton-picking, crashing, damn, damned, dead, deadly, definite, downright, dreadful, fair, flat, flat-out, out-and-out, outright, perfect, plumb, profound, pure, rank, regular, sheer, simple, stark, stone, straight-out, thorough, thoroughgoing, total, unadulterated, unalloyed, unconditional, unmitigated, unqualified, utter, veryRelated Words authentic, classic, genuine, real, veritable; constant, endless, eternal, perpetual, undying, unremitting; extreme, unrestricted; confirmed, habitual, hopeless, inveterate; extraordinary, frightful, horrible, huge, main, superlative, supreme, surpassing, terrible, terrificNear Antonyms doubtful, dubious, equivocal, qualified, questionable, restricted, uncertain