in the dark

Idioms  

1. In secret, in concealment, as in This agreement was concluded in the dark . [Early 1600s]

2. In a state of ignorance, uninformed, as in I was in the dark about their plans . This metaphor often appears in the locution keep someone in the dark , meaning “deliberately keep someone uninformed,” as in They kept me in the dark about their plans . [Late 1600s] For an antonym, see in the know .

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