read between the lines

Cultural  

1. To pay attention to what is implied in writing or in speech.

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read between the lines Idioms  

1. Perceive or detect a hidden meaning, as in They say that everything's fine, but reading between the lines I suspect they have some marital problems. This term comes from cryptography, where in one code reading every second line of a message gives a different meaning from that of the entire text. [Mid-1800s]

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