An agreement is a formal decision about future action which is made by two or more countries, groups, or people.

Agreement on something is a joint decision that a particular course of action should be taken.

Agreement with someone means having the same opinion as they have.

Agreement to a course of action means allowing it to happen or giving it your approval.

If there is agreement between two accounts of an event or two sets of figures, they are the same or are consistent with each other.

In grammar, agreement refers to the way that a word has a form appropriate to the number or gender of the noun or pronoun it relates to.