asylum back door back stairs back way cache concealment corner cover covert covert way coverture cranny cubby cubbyhole dark corner den dugout ejection seat emergency exit escalier derobe escape hatch escape route fire escape foxhole funk hole hideaway hideout hidey hole hiding hiding place hole inflatable slide lair life buoy life net life raft lifeboat lifeline niche nook recess refuge retreat sally port sanctuary secret exit secret passage secret place secret staircase side door slide stash undercovert underground underground railroad underground route