underground

Synonyms: below ground buried covered in the recesses subterranean subterrestrial sunken underfoot

Antonyms: aboveground ground sky

Synonyms: alternative avant-garde clandestine concealed covert experimental hidden hush-hush on the qt on the sly private radical resistant resistive revolutionary surreptitious unbowed unconventional undercover under wraps unusual

Antonyms: authorized condoned known legal public