1 underground /ˈʌndɚˌgraʊnd/ adjective Learner's definition of UNDERGROUND
2
always used before a noun : secret and usually illegal地下的;秘密的;非法的 3
always used before a noun : of, relating to, or produced in a social and artistic world that is different and separate from the main part of society标新立异的;小众的 2 underground /ˌʌndɚˈgraʊnd/ adverb Learner's definition of UNDERGROUND
1
: below the surface of the earth在地(面)下 2
: in or into a place that is hidden or secret : out of the view of the public隐秘地;隐蔽地;秘密地 3 underground /ˈʌndɚˌgraʊnd/ noun Learner's definition of UNDERGROUND
1
British : a system of trains that run below the ground in a large city : subway地铁 [singular]
[noncount]
2
the underground : a group of people who secretly work to oppose or overthrow a government(反政府的)地下组织