| under wraps(expression, cover, obscure, dark, equivocal) |
| underground(obscure, secret, unknown, hidden, concealed) |
| underhand(adjective, clandestine, underground) |
| undetected(obscure, dark, secret, unknown, hidden) |
| unpublished(obscure, unknown, clandestine, underground, unrevealed) |
| unseen(obscure, dark, unknown, hidden, imperceptible) |
| able |
| abstruse(obscure, dark, secret, unknown, hidden) |
| ambiguous(cover, obscure, dark, unknown, equivocal) |
| buried(cover, obscure, dark, unknown, hidden) |
| cabalistic |
| censored |
| closed |
| clouded(obscure, dark, unknown, hidden, concealed) |
| covered(obscure, secret, unknown, hidden, concealed) |
| deep(obscure, unknown, clandestine, underground, unrevealed) |
| disguised(obscure, unknown, hidden, imperceptible, concealed) |
| eclipsed(obscure, dark, secret, unknown, hidden) |
| faceless |
| hermetical(obscure, dark, secret, unknown, hidden) |