Treacherous

a.

1.

Like a traitor; involving treachery; violating allegiance or faith pledged; traitorous to the state or sovereign; perfidious in private life; betraying a trust; faithless. Loyal father of a treacherous son. - Shak. The treacherous smile, a mask for secret hate. - Cowper.

Adj.	1.	treacherous - dangerously unstable and unpredictable; "treacherous winding roads"; "an unreliable trestle" Synonyms: unreliable
	2.	treacherous - tending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans; "Punic faith"; "the perfidious Judas"; "the fiercest and most treacherous of foes"; "treacherous intrigues" Synonyms: perfidious, punic

Machiavellian, Punic, ambidextrous, artful, calculating, chancy, chiseling, collusive, covinous, crafty, crooked, cunning, dangerous, deceitful, deceptive, desultory, dishonest, disloyal, double, double-crossing, double-dealing, double-faced, double-minded, double-tongued, doublehearted, doubtful, dubious, duplicitous, faithless, false, false-principled, falsehearted, finagling, fraudulent, furtive, guileful, hairy, hazardous, indirect, infirm, insecure, insidious, insubstantial, jeopardous, misleading, perfidious, perilous, precarious, precariousness, provisional, recreant, risky, rocky, scheming, shaky, sharp, shifting, shifty, slippery, sneaky, surreptitious, temporary, tentative, ticklish, tottery, traitorous, trickish, tricky, two-faced, uncertain, undependable, underhand, underhanded, unfaithful, unfaithworthy, unhealthy, unloyal, unpredictable, unreliable, unsafe, unsolid, unsound, unstable, unsteadfast, unsteady, unsubstantial, unsure, untrue, untrustworthy, wicked, wily