Synonyms to waiting concealed

furtive, artful, back-door, backstairs, calculating, chiseling, clandestine, collusive, conspiratorial, covert, covinous, crafty, cunning, deceitful, doggo, false, falsehearted, feline, finagling, foxy, fraudulent, guileful, hidden, hidden out, hidlings, hole-and-corner, hugger-mugger, in ambush, in hiding, in the wings, indirect, insidious, lurking, on tiptoe, private, privy, prowling, pussyfoot, pussyfooted, quiet, scheming, secret, secretive, sharp, shifty, skulking, slinking, slinky, slippery, sly, sneaking, sneaky, stealing, stealthy, surreptitious, treacherous, trickish, tricky, two-faced, under cover, under the table, under-the-counter, under-the-table, undercover, underground, underhand, underhanded, unobtrusive, untrustworthy, wily, abeyant, about to be, already in sight, approaching, at hand, between the lines, brewing, close, close at hand, coming, cryptic, delitescent, dormant, esoteric, forthcoming, future, gathering, going to happen, hibernating, immediate, imminent, impendent, impending, in danger imminent, in hi