Meaning : Dangerously unstable and unpredictable.
Example :
Treacherous winding roads.
An unreliable trestle.
Synonyms : unreliable
Meaning : Tending to betray. Especially having a treacherous character as attributed to the Carthaginians by the Romans.
Example :
Punic faith.
The perfidious Judas.
The fiercest and most treacherous of foes.
Treacherous intrigues.
Synonyms : perfidious, punic