1
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Phrase(s): read between the lines
Fig. to infer something (from something else); to try to understand what is meant by something that is not written explicitly or openly. • After listening to what she said, if you read between the lines, you can begin to see what she really means. • Don’t believe everything you read literally. Learn to read between the lines.
McGrawhill's American Idioms And Phrasal Verbs
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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. [Mid1800s]
American Heritage Idioms