thistledown

n [U] light fluff that contains thistle seeds and is blown from thistle plants by the wind 蓟种子冠毛: as light as thistledown 轻如蓟的冠毛.

thinking-cap, thinly, thinner, thinness, third, third degree, third degree burn, third party, third-party insurance, third-rate, thirdly, thirst, thirstily, thirsty, thirteen, thirteenth, thirtieth, thirty, this, thistle, thither, tho', thole, Thomas Edison, thong, thorax, thorn, Thorne Middle School, thorny, thorough, thoroughbred, thoroughfare, thoroughgoing, thoroughly, thoroughness, those, thou, though, though (also tho), thought,