Precarious

a.	1.	Depending on the will or pleasure of another; held by courtesy; liable to be changed or lost at the pleasure of another; as, precarious privileges.
	2.	Held by a doubtful tenure; depending on unknown causes or events; exposed to constant risk; not to be depended on for certainty or stability; uncertain; as, a precarious state of health; precarious fortunes.

Adj.	1.	precarious - affording no ease or reassurance; "a precarious truce" Synonyms: unstable
	2.	precarious - fraught with danger; "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" Synonyms: parlous, perilous, touch-and-go
	3.	precarious - dangerously insecure; "a precarious footing on the ladder"
	4.	precarious - not secure; beset with difficulties; "a shaky marriage" Synonyms: shaky

ambiguous, borderline, chancy, delicate, desultory, dicey, difficult, doubtful, dubious, equivocal, hairy, hazardous, iffy, indecisive, infirm, insecure, insubstantial, on slippery ground, on thin ice, open, problematic, provisional, questionable, sensitive, shaky, shifting, shifty, slippery, slippy, temporary, tentative, ticklish, touch-and-go, touchy, treacherous, tricky, uncertain, undependable, unfaithworthy, unpredictable, unreliable, unsettled, unsolid, unsound, unstable, unsteadfast, unsteady, unsubstantial, unsure, untrustworthy