Main entry: unstable, precarious
Definition: affording no ease or reassurance
Usage: a precarious truce
Main entry: perilous, parlous, precarious, touch-and-go
Definition: fraught with danger
Usage: dangerous waters; a parlous journey on stormy seas; a perilous voyage across the Atlantic in a small boat; the precarious life of an undersea diver; dangerous surgery followed by a touch-and-go recovery
Main entry: precarious, shaky
Definition: not secure; beset with difficulties
Usage: a shaky marriage