Meaning:

Guess what someone's real thoughts, feelings, or intentions from what you hear or read.

If you read between the lines, you understand the real meaning of something a person says or writes
even though you are not given details.

Example:

Linda tried to be cheerful and said she was okay, but reading between the lines, I could see she was really upset.

They didn't say directly it was our fault, but it was easy to read between the lines. (It was easy to guess they meant it.)

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