marked by quiet and caution and secrecy; taking pains to avoid being observed; "a furtive manner"; "a lurking prowler"; "a sneak attack"; "stealthy footsteps"; "a surreptitious glance at his watch"; "someone skulking in the shadows"
{i} one who acts in a shifty and underhanded manner, base or contemptible person; informer (Slang); thief; act of sneaking
stead of sneaking around spying on the neighbor's house" put, bring, or take in a secretive or furtive manner; "sneak a look"; "sneak a cigarette