- Like a traitor; involving treachery; violating
allegiance or faith pledged; traitorous to the state or sovereign;
perfidious in private life; betraying a trust; faithless.
Meaning of 'treacherous' (Princeton's WordNet)
1 . treacherous
[ s]
Meaning (1): - dangerously unstable and unpredictable
Example in sentence:
an unreliable trestle;
treacherous winding roads
Meaning (2): - tending to betray; especially having a treacherous character as attributed to the Carthaginians by the Romans