"bend forward," Old English stupian "to bow, bend" (cognate with Middle Dutch stupen "to bow, bend"), from Proto-Germanic *stup-, from PIE *(s)teu- (see steep (adj.)). Figurative sense of "condescend" is from 1570s. Sense of "swoop" is first recorded 1570s in falconry.
"raised open platform at the door of a house," 1755, American and Canadian, from Dutch stoep "flight of steps, doorstep, stoop," from Middle Dutch, from Proto-Germanic *stopo "step" (see step).
A stupid person: ''Don't call me stupe,'' Humphrey said/ Surprised that we're not total stupes? (1762+)