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treacherous - definition and synonyms

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adjective     treacherous pronunciation in British English
  1. 1
    someone who is treacherous pretends that they support you but secretly tries to harm you, for example by helping an enemy

    treacherous behaviour/thoughts

  2. 2
    very dangerous, especially because the dangers are not obvious

    Is it wise to go out in this treacherous weather?

    a treacherous road/path/journey

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a rainbow produced when water droplets in the air reflect light from the moon rather than the sun

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