blunder

noun

1
utter impulsively
He blurted out the secret
He blundered his stupid ideas
2
make one's way clumsily or blindly
He fumbled towards the door
3
commit a faux pas or a fault or make a serious mistake
I blundered during the job interview

Also useful for “blunder”:Unscrambler— Rearrange the letters in “blunder”