clandestine Synonyms

secret surreptitious underground hidden private stealthy furtive undercover hush-hush secretive covert sly concealed cloak-and-dagger underhand hugger-mugger hole-and-corner behind-the-scenes sub-rosa under-the-table backroom back room subversive surrey underfoot undergrow underhanded underneath unseen veiled back channel belowground black-market undisclosed top secret unannounced under the counter under wraps unpublicized unpublished unreported unrevealed sneakingly unapparent off the record low profile low-key nonpublic clandestinely conspiratorial