| clandestine(adjective, adverb, secret, private, hidden) |
| confidentially |
| covert(adjective, secret, private, hidden, sneaky) |
| dishonestly |
| guilefully |
| hidden(adjective, secret, private, sneaky, covert) |
| hole-and-corner(adjective, secret, private, hidden, fraudulent) |
| hush-hush(adjective, adverb, secret, clandestine, quietly) |
| in camera(expression, adverb, clandestine, quietly, personally) |
| in confidence(expression, adverb, quietly, secretly, personally) |
| in disguise(expression, adverb, furtively, incognito) |
| in holes and corners(expression, idiom, adverb, clandestine, quietly) |
| in secret(expression, idiom, adverb) |
| in strict confidence(expression, adverb, quietly, secretly, personally) |
| insidiously(adverb, quietly, secretly, personally, privately) |
| intimately(adverb, quietly, secretly, personally, privately) |
| knowingly |
| obscurely(adverb, quietly, secretly, personally, privately) |
| privily(adverb, quietly, secretly, personally, privately) |
| slick |