no ifs or buts

Also, no ifs, ands, or buts. No reservations, restrictions, or excuses, as in You'd better be there tomorrow, and no ifs, ands, or buts about it. This expression uses the conjunctions to stand for the conditions and objections that they introduce. The earliest phrase to appear was ifs and ands in the 1600s. This phrase is actually an emphatic redundancy, for and often meant "if." But was tacked on to this pair soon afterward.