Verb

To harmonize in opinion, statement, or action; to be in unison or concord; to be or become united or consistent; to concur.

all parties agree in the expediency of the law.

* {{quote-book, year=1594

, author=Thomas Lodge , title=The wounds of civil war: Lively set forth in the true tragedies of Marius and Scilla , page=46 , passage=You know that in so great a state as this, Two mightie foes can never well agree .}}

* (rfdate) Shakespeare

If music and sweet poetry agree .

* (rfdate) Mark xiv. 56.

Their witness agreed not together.

* (rfdate) Sir T. Browne

The more you agree together, the less hurt can your enemies do you.

To yield assent; to accede;—followed by to.

to agree to an offer, or to opinion.

(transitive, UK, Irish) To yield assent to; to approve.

* {{quote-book, year=1666

, author=Samuel Pepys , title=The Diary of Samuel Pepys , page=88 , passage=... and there, after a good while in discourse, we did agree a bargain of £5,000 with Sir Roger Cuttance for my Lord Sandwich for silk, cinnamon, ...}}

* {{quote-book, year=2005

, author=Paddy McNutt , title=Law, economics and antitrust: towards a new perspective , page=59 , passage=The essential idea is that parties should enter the market, choose their contractors, set their own terms and agree a bargain.}}

* 2011 April 3, John Burke, in The Sunday Business Post :

Bishops agree sex abuse rules

To make a stipulation by way of settling differences or determining a price; to exchange promises; to come to terms or to a common resolve; to promise.

* (rfdate) Matt. v. 25.

Agree with thine adversary quickly.

* (rfdate) Matt. xx. 13.

Didst not thou agree with me for a penny ?

To be conformable; to resemble; to coincide; to correspond.

the picture does not agree with the original; the two scales agree exactly.

To suit or be adapted in its effects; to do well.

the same food does not agree with every constitution.

(grammar) To correspond to in gender, number, case, or person.

(legal) To consent to a contract or to an element of a contract.

Verb

(cooperat)

To work or act together, especially for a common purpose or benefit.

* {{quote-news, year=2012, date=November 7, author=Matt Bai, title=Winning a Second Term, Obama Will Confront Familiar Headwinds, work=New York Times citation

, passage=In polling by the Pew Research Center in November 2008, fully half the respondents thought the two parties would cooperate more in the coming year, versus only 36 percent who thought the climate would grow more adversarial. }}

To allow for mutual unobstructed action

To function in harmony, side by side

To engage in economic cooperation.