underground
//ˌʌndəˈɡraʊnd//
Adjective
undergroundCanonical form
1
Located or operating beneath the surface of the earth.
The city has an underground parking lot.
2
Secret or hidden; operating outside the establishment or mainstream.
The underground music scene was thriving in the city.
Synonym
Antonym
Adverb
undergroundCanonical form
1
Beneath the surface of the ground.
The moles live underground.
2
In or into secrecy or hiding.
The activists went underground to avoid arrest.
Noun
1
A subway system, especially the one in London.
I take the underground to work every day.
2
A secret group or movement organized to resist or oppose those in power.
During the war, he joined the underground to fight against the occupation.