Learner's definition of AGREEMENT
1 a : the act of agreeing
b : a situation in which people share the same opinion: a situation in which people agree
Any changes to the plan require the agreement of everyone involved.
We were surprised by his agreement to participate. [=we were surprised that he agreed to participate]
She nodded her head in agreement. [=to show that she agreed]
There is wide/widespread/universal agreement on this issue.
Everyone seems to be in agreement [=seems to agree] about/on the need for reform, but there is much disagreement about how to achieve it.
They have been unable to reach agreement about how to achieve reform.
2 a : an arrangement, contract, etc., by which people agree about what is to be done
b : a written record of such an agreement
I thought we had an agreement.
a formal/contractual agreement
Their agreement expires next year.
He has to return the property under the terms of an agreement he has with the original owner.
a peace agreement
a trade agreement
They have come to an agreement. = They have reached an agreement.
3 [noncount], grammar : the fact or state of being alike in gender, number, case, or person: the fact or state of agreeing grammatically