Source : Webster's Revised Unabridged Dictionary (1913)

Agree \A*gree"\, v. i. [imp. & p. p. {Agreed}; p. pr. & vb. n.
   {Agreeing}.] [F. agr['e]er to accept or receive kindly, fr.
   [`a] gr['e]; [`a] (L. ad) + gr['e] good will, consent,
   liking, fr. L. gratus pleasing, agreeable. See {Grateful}.]
   1. To harmonize in opinion, statement, or action; to be in
      unison or concord; to be or become united or consistent;
      to concur; as, all parties agree in the expediency of the
      law.

            If music and sweet poetry agree.      --Shak.

            Their witness agreed not together.    --Mark xiv.
                                                  56.

            The more you agree together, the less hurt can your
            enemies do you.                       --Sir T.
                                                  Browne.

   2. To yield assent; to accede; -- followed by to; as, to
      agree to an offer, or to opinion.

   3. 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.

            Agree with thine adversary quickly.   --Matt. v. 25.

            Didst not thou agree with me for a penny ? --Matt.
                                                  xx. 13.

   4. To be conformable; to resemble; to coincide; to
      correspond; as, the picture does not agree with the
      original; the two scales agree exactly.

   5. To suit or be adapted in its effects; to do well; as, the
      same food does not agree with every constitution.

   6. (Gram.) To correspond in gender, number, case, or person.

   Note: The auxiliary forms of to be are often employed with
         the participle agreed. ``The jury were agreed.''
         --Macaulay. ``Can two walk together, except they be
         agreed ?'' --Amos iii. 3. The principal intransitive
         uses were probably derived from the transitive verb
         used reflexively. ``I agree me well to your desire.''
         --Ld. Berners.

   Syn: To assent; concur; consent; acquiesce; accede; engage;
        promise; stipulate; contract; bargain; correspond;
        harmonize; fit; tally; coincide; comport.

Agre \A*gre"\, Agree \A*gree"\, adv. [F. [`a] gr['e]. See
   {Agree}.]
   In good part; kindly. [Obs.] --Rom. of R.

Agree \A*gree"\, v. t.
   1. To make harmonious; to reconcile or make friends. [Obs.]
      --Spenser.

   2. To admit, or come to one mind concerning; to settle; to
      arrange; as, to agree the fact; to agree differences.
      [Obs.]

Source : WordNet®

agree
     v 1: be in accord; be in agreement; "We agreed on the terms of
          the settlement"; "I can't agree with you!"; "I hold with
          those who say life is sacred"; "Both philosophers
          concord on this point" [syn: {hold}, {concur}, {concord}]
          [ant: {disagree}]
     2: consent or assent to a condition, or agree to do something;
        "She agreed to all my conditions"; "He agreed to leave her
        alone"
     3: be compatible, similar or consistent; coincide in their
        characteristics; "The two stories don't agree in many
        details"; "The handwriting checks with the signature on
        the check"; "The suspect's fingerprints don't match those
        on the gun" [syn: {match}, {fit}, {correspond}, {check}, {jibe},
         {gibe}, {tally}] [ant: {disagree}]
     4: go together; "The colors don't harmonize"; "Their ideas
        concorded" [syn: {harmonize}, {harmonise}, {consort}, {accord},
         {concord}, {fit in}]
     5: show grammatical agreement; "Subjects and verbs must always
        agree in English"
     6: be agreeable or suitable; "White wine doesn't agree with me"
     7: achieve harmony of opinion, feeling, or purpose; "No two of
        my colleagues would agree on whom to elect chairman"