noun |
adj |
verb |
adv |
(adj) secret, undercover, underground, surreptitious, hole-and-corner, hugger-mugger, hush-hush, clandestine
conducted with or marked by hidden aims or methods
clandestine intelligence operations; cloak-and-dagger activities behind enemy lines; hole-and-corner intrigue; secret missions; a secret agent; secret sales of arms; surreptitious mobilization of troops; an undercover investigation; underground resistance