open book

noun

: something that is widely or fully known : a thing completely free from mystery or concealment
her life is an open book

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Dictionary Entries Near open book

openbill

open book

open-book examination

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“Open book.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/open%20book. Accessed 23 Dec. 2024.

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