Synonyms of stupidly

2 Syllables
feebly, rashly, badly
3 Syllables
faultily, ineptly, stubbornly, naively, foolishly
4 Syllables
imprudently, obtusely, shortsightedly, credulously, blunderingly, erroneously, imperfectly, maladroitly, unskillfully, ferociously, insanely, carelessly
5 Syllables
idiotically, abominably, irrationally, unreasonably