Perilous

a.	1.	Full of, attended with, or involving, peril; dangerous; hazardous; as, a perilous undertaking. Infamous hills, and sandy, perilous wilds. - Milton.
	2.	Daring; reckless; dangerous. For I am perilous with knife in hand. - Chaucer.

Adj.

1.

perilous - 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, touch-and-go, precarious

alarming, bad, chancy, dangersome, delicate, desultory, explosive, fraught with danger, hairy, infirm, insubstantial, jeopardous, parlous, periculous, provisional, serious, shaky, shifting, shifty, slippery, susceptible, temporary, tentative, threatening, ticklish, tottery, touchy, treacherous, ugly, uncertain, undependable, unfaithworthy, unhealthy, unreliable, unsolid, unsound, unstable, unsteadfast, unsteady, unsubstantial, unsure, untrustworthy, vulnerable, wicked