means “heart to heart.” (Latin, ad corda.) If two persons like and dislike the same things, they are heart to heart with each other.
Similarly, “con-cord” heart with heart; “dis-cord,” heart divided from heart; “re-cord” properly means to recollect—i.e., re-cordare, to bring again to the mind or heart; then to set down in writing for the purpose of recollecting.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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