means a thin tube, traditionally of paper or plastic, used to suck up a drink — or, separately, the dried stalks of grain left after threshing.

from From Old English 'strēaw,' meaning the dried stems of cereal plants, kin to Old High German 'strō' and tied to the root of 'strew' — for straw was literally the stuff you scattered across floors and beds. The drinking sense came much later, named because the first such tubes were exactly that: hollow stalks of dried grain, pressed into service before paper and plastic ever appeared.