numskull (also numbskull)

n (infml derog 口, 贬) stupid person 笨蛋; 傻瓜.

nullification, nullify, nullity, numb, number, number one, numberless, numbly, numbness, numeracy, numeral, numerate, numeration, numerator, numerical, numerically, numerous, numinous, numismatics, numismatist, nun, nuncio, nunnery, nuptial, nuptials, nurse, nursery, nursery nurse, nursery rhyme, nursery school, nursery slope, nursery stakes, nurseryman, nursing, nursing mother, nursing-home, nurture, nut, nut-brown, nut-case,