speedway

n (a) [C] track for fast driving and racing, esp by motor-bikes 赛车跑道（尤指摩托车的）. (b) [U] sport of racing motor-bikes on such a track 摩托车赛: Do you like speedway? 你喜欢摩托车赛吗? (c) [C] (US) road on which fast driving is allowed 高速公路.

speech therapist, speech therapy, speech-day, speechify, speechless, speechlessly, speechlessness, speed, speed limit, speed merchant, speed trap, speed up, speed-boat, speed-indicator, speed-up, speedboat, speedily, speediness, speeding, speedometer, speedwell, speedy, speleological (also spelaeological), speleologist (also spelaeologist), speleology (also spelaeology), spell, spellbinder, spellbinding, spellbound, speller, spelling, spelt, spelunker, spend, spend...time (in) doing, spender, spending, spendthrift, spent, sperm,