'flub' originates from American English, possibly an alteration of 'flop' or 'fluff', where 'flop' meant 'to fall or fail' and 'fluff' meant 'to make a mistake'.

'flub' emerged in the early 20th century as a colloquial term in American English, evolving from similar-sounding words like 'flop'.

Initially, it meant 'to make a mistake', and this meaning has largely remained the same in modern usage.