marked by quiet and caution and secrecy; taking pains to avoid being observed; a furtive manner; a sneak attack; stealthy footsteps; a surreptitious glance at his watch
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
[ Syn: clandestine , cloak-and-dagger , hole-and-corner , hugger-mugger , hush-hush , secret , undercover , underground ]