1 under the surface of the ground 在地面之下的；地下的: an underground car park地下停车场
2 secret or illegal 秘密的；非法的；地下的: an underground radio station地下电台
*underground²
/ˌʌndəˈgraʊnd ||; ˈʌndɚˈgraυnd/adv
1 under the surface of the ground 在地面之下: The cables all run underground.电缆都铺设在地下。
2 into a secret place 进入秘密的地方: She went underground to escape from the police.她转入地下以避开警方的搜捕。
*underground³
/ˈʌndəgraʊnd ||; ˈʌndɚˌgraυnd/(US 美 subway) noun [sing] a railway system under the ground 地下铁路系统；地铁 In London the underground railway is called the underground or the tube. 在伦敦，地下铁路叫做the underground或the tube。