What does the word treacherous mean?

Usage examples for treacherous

  1. What can be done with these treacherous people? – Ismailia by Samuel W. Baker
  2. We were all four in a direct line one below the other, and the two last on the rope were placed perforce directly beneath the treacherous crag. – Above the Snow Line by Clinton Thomas Dent
  3. Then again the young King had Zavis done to death in treacherous manner, while the condition of Bohemia as an ordered State went from bad to worse. – From a Terrace in Prague by Lieut.-Col. B. Granville Baker