Ad Idem

Meeting of the minds (also referred to as mutual assent or consensus ad idem) is a phrase in contract law used to describe the intentions of the parties forming the contract. In particular it refers to the situation where there is a common understanding in the formation of the contract. This condition or element is often considered a necessary requirement to the formation of a contract.
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Of same mind
ie as one; agreed eg the parties are ad idem on this point

Of the same mind