n. 25B6; noun he shook his head at his blunder : MISTAKE, error, gaffe, slip, oversight, faux pas; informal botch, slip-up, boo-boo; Brit. informal clanger, boob; N. Amer. informal blooper.
25B6; verb
the government admitted it had blundered : MAKE A MISTAKE, err, miscalculate, bungle, trip up, be wrong; informal slip up, screw up, blow it, goof; Brit. informal boob.
she blundered down the steps : STUMBLE, lurch, stagger, flounder, struggle, fumble, grope.